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path: root/apps/interpreters/bas/statement.c
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#include <nuttx/config.h>

#include "statement.h"

#define _(String) String

struct Value *stmt_CALL(struct Value *value)
{
  ++pc.token;
  if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGPROCIDENT);
  if (pass==DECLARE)
  {
    if (func(value)->type==V_ERROR) return value;
    else Value_destroy(value);
  }
  else
  {
    if (pass==COMPILE)
    {
      if
      (
        Global_find(&globals,pc.token->u.identifier,(pc.token+1)->type==T_OP)==0
      ) return Value_new_ERROR(value,UNDECLARED);
    }
    if (pc.token->u.identifier->sym->type!=USERFUNCTION && pc.token->u.identifier->sym->type!=BUILTINFUNCTION) return Value_new_ERROR(value,TYPEMISMATCH1,"variable","function");
    func(value);
    if (Value_retype(value,V_VOID)->type==V_ERROR) return value;
    Value_destroy(value);
  }
  return (struct Value*)0;
}

struct Value *stmt_CASE(struct Value *value)
{
  struct Pc statementpc=pc;

  if (pass==DECLARE || pass==COMPILE)
  {
    struct Pc *selectcase,*nextcasevalue;

    if ((selectcase=findLabel(L_SELECTCASE))==(struct Pc*)0) return Value_new_ERROR(value,STRAYCASE);
    for (nextcasevalue=&selectcase->token->u.selectcase->nextcasevalue; nextcasevalue->line!=-1; nextcasevalue=&nextcasevalue->token->u.casevalue->nextcasevalue);
    *nextcasevalue=pc;
    if (pass==COMPILE) pc.token->u.casevalue->endselect=selectcase->token->u.selectcase->endselect;
    pc.token->u.casevalue->nextcasevalue.line=-1;
    ++pc.token;
    switch (statementpc.token->type)
    {
      case T_CASEELSE: break;
      case T_CASEVALUE:
      {
        struct Pc exprpc;

        do
        {
          if (pc.token->type==T_IS)
          {
            ++pc.token;
            switch (pc.token->type)
            {
              case T_LT:
              case T_LE:
              case T_EQ:
              case T_GE:
              case T_GT:
              case T_NE: break;
              default: return Value_new_ERROR(value,MISSINGRELOP);
            }
            ++pc.token;
            exprpc=pc;
            if (eval(value,"`is'")->type==V_ERROR) return value;
            if (Value_retype(value,selectcase->token->u.selectcase->type)->type==V_ERROR)
            {
              pc=exprpc;
              return value;
            }
            Value_destroy(value);
          }

          else /* value or range */
          {
            exprpc=pc;
            if (eval(value,"`case'")->type==V_ERROR) return value;
            if (Value_retype(value,selectcase->token->u.selectcase->type)->type==V_ERROR)
            {
              pc=exprpc;
              return value;
            }
            Value_destroy(value);
            if (pc.token->type==T_TO)
            {
              ++pc.token;
              exprpc=pc;
              if (eval(value,"`case'")->type==V_ERROR) return value;
              if (Value_retype(value,selectcase->token->u.selectcase->type)->type==V_ERROR)
              {
                pc=exprpc;
                return value;
              }
              Value_destroy(value);
            }

          }

          if (pc.token->type==T_COMMA) ++pc.token;
          else break;
        } while (1);
        break;
      }
      default: assert(0);
    }
  }
  else pc=pc.token->u.casevalue->endselect;
  return (struct Value*)0;
}

struct Value *stmt_CHDIR_MKDIR(struct Value *value)
{
  int res=-1,err=-1;
  struct Pc dirpc;
  struct Pc statementpc=pc;

  ++pc.token;
  dirpc=pc;
  if (eval(value,_("directory"))->type==V_ERROR || Value_retype(value,V_STRING)->type==V_ERROR) return value;
  if (pass==INTERPRET)
  {
    switch (statementpc.token->type)
    {
      case T_CHDIR: res=chdir(value->u.string.character); break;
      case T_MKDIR: res=mkdir(value->u.string.character,0777); break;
      default: assert(0);
    }
    err=errno;
  }
  Value_destroy(value);
  if (pass==INTERPRET && res==-1)
  {
    pc=dirpc;
    return Value_new_ERROR(value,IOERROR,strerror(err));
  }
  return (struct Value*)0;
}

struct Value *stmt_CLEAR(struct Value *value)
{
  if (pass==INTERPRET)
  {
    Global_clear(&globals);
    FS_closefiles();
  }
  ++pc.token;
  return (struct Value*)0;
}

struct Value *stmt_CLOSE(struct Value *value)
{
  int hasargs=0;
  struct Pc chnpc;

  ++pc.token;
  while (1)
  {
    chnpc=pc;
    if (pc.token->type==T_CHANNEL) { hasargs=1; ++pc.token; }
    if (eval(value,(const char*)0)==(struct Value*)0)
    {
      if (hasargs) return Value_new_ERROR(value,MISSINGEXPR,_("channel"));
      else break;
    }
    hasargs=1;
    if (value->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
    if (pass==INTERPRET && FS_close(value->u.integer)==-1)
    {
      Value_destroy(value);
      pc=chnpc;
      return Value_new_ERROR(value,IOERROR,FS_errmsg);
    }
    if (pc.token->type==T_COMMA) ++pc.token;
    else break;
  }
  if (!hasargs && pass==INTERPRET) FS_closefiles();
  return (struct Value*)0;
}

struct Value *stmt_CLS(struct Value *value)
{
  struct Pc statementpc=pc;

  ++pc.token;
  if (pass==INTERPRET && FS_cls(STDCHANNEL)==-1)
  {
    pc=statementpc;
    return Value_new_ERROR(value,IOERROR,FS_errmsg);
  }
  return (struct Value*)0;
}

struct Value *stmt_COLOR(struct Value *value)
{
  int foreground=-1,background=-1;
  struct Pc statementpc=pc;

  ++pc.token;
  if (eval(value,(const char*)0))
  {
    if (value->type==V_ERROR || (pass!=DECLARE && Value_retype(value,V_INTEGER)->type==V_ERROR)) return value;
    foreground=value->u.integer;
    if (foreground<0 || foreground>15)
    {
      Value_destroy(value);
      pc=statementpc;
      return Value_new_ERROR(value,OUTOFRANGE,_("foreground colour"));
    }
  }
  Value_destroy(value);
  if (pc.token->type==T_COMMA)
  {
    ++pc.token;
    if (eval(value,(const char*)0))
    {
      if (value->type==V_ERROR || (pass!=DECLARE && Value_retype(value,V_INTEGER)->type==V_ERROR)) return value;
      background=value->u.integer;
      if (background<0 || background>15)
      {
        Value_destroy(value);
        pc=statementpc;
        return Value_new_ERROR(value,OUTOFRANGE,_("background colour"));
      }
    }
    Value_destroy(value);
    if (pc.token->type==T_COMMA)
    {
      ++pc.token;
      if (eval(value,(const char*)0))
      {
        int bordercolour=-1;

        if (value->type==V_ERROR || (pass!=DECLARE && Value_retype(value,V_INTEGER)->type==V_ERROR)) return value;
        bordercolour=value->u.integer;
        if (bordercolour<0 || bordercolour>15)
        {
          Value_destroy(value);
          pc=statementpc;
          return Value_new_ERROR(value,OUTOFRANGE,_("border colour"));
        }
      }
      Value_destroy(value);
    }
  }
  if (pass==INTERPRET) FS_colour(STDCHANNEL,foreground,background);
  return (struct Value*)0;
}

struct Value *stmt_DATA(struct Value *value)
{
  if (DIRECTMODE) return Value_new_ERROR(value,NOTINDIRECTMODE);
  if (pass==DECLARE)
  {
    *lastdata=pc;
    (lastdata=&(pc.token->u.nextdata))->line=-1;
  }
  ++pc.token;
  while (1)
  {
    if (pc.token->type!=T_STRING && pc.token->type!=T_DATAINPUT) return Value_new_ERROR(value,MISSINGDATAINPUT);
    ++pc.token;
    if (pc.token->type!=T_COMMA) break;
    else ++pc.token;
  }
  return (struct Value*)0;
}

struct Value *stmt_DEFFN_DEFPROC_FUNCTION_SUB(struct Value *value)
{
  if (pass==DECLARE || pass==COMPILE)
  {
    struct Pc statementpc=pc;
    struct Identifier *fn;
    int proc;
    int args=0;

    if (DIRECTMODE) return Value_new_ERROR(value,NOTINDIRECTMODE);
    proc=(pc.token->type==T_DEFPROC || pc.token->type==T_SUB);
    ++pc.token;
    if (pc.token->type!=T_IDENTIFIER)
    {
      if (proc) return Value_new_ERROR(value,MISSINGPROCIDENT);
      else return Value_new_ERROR(value,MISSINGFUNCIDENT);
    }
    fn=pc.token->u.identifier;
    if (proc) fn->defaultType=V_VOID;
    ++pc.token;
    if (findLabel(L_FUNC))
    {
      pc=statementpc;
      return Value_new_ERROR(value,NESTEDDEFINITION);
    }
    Auto_variable(&stack,fn);
    if (pc.token->type==T_OP) /* arguments */
    {
      ++pc.token;
      while (1)
      {
        if (pc.token->type!=T_IDENTIFIER)
        {
          Auto_funcEnd(&stack);
          return Value_new_ERROR(value,MISSINGFORMIDENT);
        }
        if (Auto_variable(&stack,pc.token->u.identifier)==0)
        {
          Auto_funcEnd(&stack);
          return Value_new_ERROR(value,ALREADYDECLARED);
        }
        ++args;
        ++pc.token;
        if (pc.token->type==T_COMMA) ++pc.token;
        else break;
      }
      if (pc.token->type!=T_CP)
      {
        Auto_funcEnd(&stack);
        return Value_new_ERROR(value,MISSINGCP);
      }
      ++pc.token;
    }

    if (pass==DECLARE)
    {
      enum ValueType *t=args ? malloc(args*sizeof(enum ValueType)) : (enum ValueType*)0;
      int i;

      for (i=0; i<args; ++i) t[i]=Auto_argType(&stack,i);
      if (Global_function(&globals,fn,fn->defaultType,&pc,&statementpc,args,t)==0)
      {
        free(t);
        Auto_funcEnd(&stack);
        pc=statementpc;
        return Value_new_ERROR(value,REDECLARATION);
      }
      Program_addScope(&program,&fn->sym->u.sub.u.def.scope);
    }
    pushLabel(L_FUNC,&statementpc);
    if (pc.token->type==T_EQ) return stmt_EQ_FNRETURN_FNEND(value);
  }
  else pc=(pc.token+1)->u.identifier->sym->u.sub.u.def.scope.end;
  return (struct Value*)0;
}

struct Value *stmt_DEC_INC(struct Value *value)
{
  int step;

  step=(pc.token->type==T_DEC ? -1 : 1);
  ++pc.token;
  while (1)
  {
    struct Value *l,stepValue;
    struct Pc lvaluepc;

    lvaluepc=pc;
    if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGDECINCIDENT);
    if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,(pc.token+1)->type==T_OP?GLOBALARRAY:GLOBALVAR,0)==0)
    {
      return Value_new_ERROR(value,REDECLARATION);
    }
    if ((l=lvalue(value))->type==V_ERROR) return value;
    if (l->type==V_INTEGER) VALUE_NEW_INTEGER(&stepValue,step);
    else if (l->type==V_REAL) VALUE_NEW_REAL(&stepValue,(double)step);
    else
    {
      pc=lvaluepc;
      return Value_new_ERROR(value,TYPEMISMATCH5);
    }
    if (pass==INTERPRET) Value_add(l,&stepValue,1);
    Value_destroy(&stepValue);
    if (pc.token->type==T_COMMA) ++pc.token;
    else break;
  }
  return (struct Value*)0;
}

struct Value *stmt_DEFINT_DEFDBL_DEFSTR(struct Value *value)
{
  enum ValueType dsttype=V_NIL;

  switch (pc.token->type)
  {
    case T_DEFINT: dsttype=V_INTEGER; break;
    case T_DEFDBL: dsttype=V_REAL; break;
    case T_DEFSTR: dsttype=V_STRING; break;
    default: assert(0);
  }
  ++pc.token;
  while (1)
  {
    struct Identifier *ident;

    if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGVARIDENT);
    if (pc.token->u.identifier->defaultType!=V_REAL) switch (dsttype)
    {
      case V_INTEGER: return Value_new_ERROR(value,BADIDENTIFIER,_("integer"));
      case V_REAL: return Value_new_ERROR(value,BADIDENTIFIER,_("real"));
      case V_STRING: return Value_new_ERROR(value,BADIDENTIFIER,_("string"));
      default: assert(0);
    }
    ident=pc.token->u.identifier;
    ++pc.token;
    if (pc.token->type==T_MINUS)
    {
      struct Identifier i;

      if (strlen(ident->name)!=1) return Value_new_ERROR(value,BADRANGE);
      ++pc.token;
      if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGVARIDENT);
      if (strlen(pc.token->u.identifier->name)!=1) return Value_new_ERROR(value,BADRANGE);
      for (i.name[0]=tolower(ident->name[0]),i.name[1]='\0'; i.name[0]<=tolower(pc.token->u.identifier->name[0]); ++i.name[0])
      {
        Global_variable(&globals,&i,dsttype,GLOBALVAR,1);
      }
      ++pc.token;
    }
    else Global_variable(&globals,ident,dsttype,GLOBALVAR,1);
    if (pc.token->type==T_COMMA) ++pc.token;
    else break;
  }
  return (struct Value*)0;
}

struct Value *stmt_DELETE(struct Value *value)
{
  struct Pc from,to;
  int f=0,t=0;

  if (pass==INTERPRET && !DIRECTMODE) return Value_new_ERROR(value,NOTINPROGRAMMODE);
  ++pc.token;
  if (pc.token->type==T_INTEGER)
  {
    if (pass==INTERPRET && Program_goLine(&program,pc.token->u.integer,&from)==(struct Pc*)0) return Value_new_ERROR(value,NOSUCHLINE);
    f=1;
    ++pc.token;
  }
  if (pc.token->type==T_MINUS || pc.token->type==T_COMMA)
  {
    ++pc.token;
    if (pc.token->type==T_INTEGER)
    {
      if (pass==INTERPRET && Program_goLine(&program,pc.token->u.integer,&to)==(struct Pc*)0) return Value_new_ERROR(value,NOSUCHLINE);
      t=1;
      ++pc.token;
    }
  }
  else if (f==1)
  {
    to=from;
    t=1;
  }
  if (!f && !t) return Value_new_ERROR(value,MISSINGLINENUMBER);
  if (pass==INTERPRET)
  {
    Program_delete(&program,f?&from:(struct Pc*)0,t?&to:(struct Pc*)0);
  }
  return (struct Value*)0;
}

struct Value *stmt_DIM(struct Value *value)
{
  ++pc.token;
  while (1)
  {
    unsigned int capacity=0,*geometry=(unsigned int*)0;
    struct Var *var;
    struct Pc dimpc;
    unsigned int dim;
    enum ValueType vartype;

    if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGARRIDENT);
    if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,GLOBALARRAY,0)==0)
    {
      return Value_new_ERROR(value,REDECLARATION);
    }
    var=&pc.token->u.identifier->sym->u.var;
    if (pass==INTERPRET && var->dim) return Value_new_ERROR(value,REDIM);
    vartype=var->type;
    ++pc.token;
    if (pc.token->type!=T_OP) return Value_new_ERROR(value,MISSINGOP);
    ++pc.token;
    dim=0;
    while (1)
    {
      dimpc=pc;
      if (eval(value,_("dimension"))->type==V_ERROR || (pass!=DECLARE && Value_retype(value,V_INTEGER)->type==V_ERROR))
      {
        if (capacity) free(geometry);
        return value;
      }
      if (pass==INTERPRET && value->u.integer<optionbase) /* error */
      {
        Value_destroy(value);
        Value_new_ERROR(value,OUTOFRANGE,_("dimension"));
      }

      if (value->type==V_ERROR) /* abort */
      {
        if (capacity) free(geometry);
        pc=dimpc;
        return value;
      }

      if (pass==INTERPRET)
      {
        if (dim==capacity) /* enlarge geometry */
        {
          unsigned int *more;

          more=realloc(geometry,sizeof(unsigned int)*(capacity?(capacity*=2):(capacity=3)));
          geometry=more;
        }

        geometry[dim]=value->u.integer-optionbase+1;
        ++dim;
      }
      Value_destroy(value);
      if (pc.token->type==T_COMMA) ++pc.token;
      else break;
    }
    if (pc.token->type!=T_CP) /* abort */
    {
      if (capacity) free(geometry);
      return Value_new_ERROR(value,MISSINGCP);
    }

    ++pc.token;
    if (pass==INTERPRET)
    {
      struct Var newarray;

      assert(capacity);
      if (Var_new(&newarray,vartype,dim,geometry,optionbase)==(struct Var*)0)
      {
        free(geometry);
        return Value_new_ERROR(value,OUTOFMEMORY);
      }
      Var_destroy(var);
      *var=newarray;
      free(geometry);
    }
    if (pc.token->type==T_COMMA) ++pc.token; /* advance to next var */
    else break;
  }
  return (struct Value*)0;
}

struct Value *stmt_DISPLAY(struct Value *value)
{
  struct Pc statementpc=pc;

  ++pc.token;
  if (eval(value,_("file name"))->type==V_ERROR || (pass!=DECLARE && Value_retype(value,V_STRING)->type==V_ERROR)) return value;
  if (pass==INTERPRET && cat(value->u.string.character)==-1)
  {
    const char *msg=strerror(errno);

    Value_destroy(value);
    pc=statementpc;
    return Value_new_ERROR(value,IOERROR,msg);
  }
  else Value_destroy(value);
  return (struct Value*)0;
}

struct Value *stmt_DO(struct Value *value)
{
  if (pass==DECLARE || pass==COMPILE) pushLabel(L_DO,&pc);
  ++pc.token;
  return (struct Value*)0;
}

struct Value *stmt_DOcondition(struct Value *value)
{
  struct Pc dowhilepc=pc;
  int negate=(pc.token->type==T_DOUNTIL);

  if (pass==DECLARE || pass==COMPILE) pushLabel(L_DOcondition,&pc);
  ++pc.token;
  if (eval(value,"condition")->type==V_ERROR) return value;
  if (pass==INTERPRET)
  {
    int condition;

    condition=Value_isNull(value);
    if (negate) condition=!condition;
    if (condition) pc=dowhilepc.token->u.exitdo;
    Value_destroy(value);
  }
  return (struct Value*)0;
}

struct Value *stmt_EDIT(struct Value *value)
{
#ifdef CONFIG_ARCH_HAVE_VFORK
  long int line;
  struct Pc statementpc=pc;

  ++pc.token;
  if (pc.token->type==T_INTEGER)
  {
    struct Pc where;

    if (program.numbered)
    {
      if (Program_goLine(&program,pc.token->u.integer,&where)==(struct Pc*)0) return Value_new_ERROR(value,NOSUCHLINE);
      line=where.line+1;
    }
    else
    {
      if (!Program_end(&program,&where)) return Value_new_ERROR(value,NOPROGRAM);
      line=pc.token->u.integer;
      if (line<1 || line>(where.line+1)) return Value_new_ERROR(value,NOSUCHLINE);
    }
    ++pc.token;
  }
  else line=1;
  if (pass==INTERPRET)
  {
    /* variables */
    char *name;
    int chn;
    struct Program newProgram;
    const char *visual,*basename,*shell;
    struct String cmd;
    static struct
    {
      const char *editor,*flag;
    }
    gotoLine[]=
    {
      { "Xemacs", "+%ld " },
      { "cemacs", "+%ld " },
      { "emacs", "+%ld " },
      { "emori", "-l%ld " },
      { "fe", "-l%ld " },
      { "jed", "+%ld " },
      { "jmacs", "+%ld " },
      { "joe", "+%ld " },
      { "modeori", "-l%ld " },
      { "origami", "-l%ld " },
      { "vi", "-c%ld " },
      { "vim", "+%ld " },
      { "xemacs", "+%ld " }
    };
    unsigned int i;
    pid_t pid;


    if (!DIRECTMODE)
    {
      pc=statementpc;
      return Value_new_ERROR(value,NOTINPROGRAMMODE);
    }
    if ((name=mytmpnam())==(char*)0)
    {
      pc=statementpc;
      return Value_new_ERROR(value,IOERROR,_("generating temporary file name failed"));
    }
    if ((chn=FS_openout(name))==-1)
    {
      pc=statementpc;
      return Value_new_ERROR(value,IOERRORCREATE,name,FS_errmsg);
    }
    FS_width(chn,0);
    if (Program_list(&program,chn,0,(struct Pc*)0,(struct Pc*)0,value))
    {
      pc=statementpc;
      return value;
    }
    if (FS_close(chn)==-1)
    {
      pc=statementpc;
      unlink(name);
      return Value_new_ERROR(value,IOERRORCLOSE,name,FS_errmsg);
    }
    if ((visual=getenv("VISUAL"))==(char*)0 && (visual=getenv("EDITOR"))==(char*)0) visual="vi";
    basename=strrchr(visual,'/');
    if (basename==(char*)0) basename=visual;
    if ((shell=getenv("SHELL"))==(char*)0) shell="/bin/sh";
    String_new(&cmd);
    String_appendChars(&cmd,visual);
    String_appendChar(&cmd,' ');
    for (i=0; i<sizeof(gotoLine)/sizeof(gotoLine[0]); ++i)
    {
      if (strcmp(basename,gotoLine[i].editor)==0)
      {
        String_appendPrintf(&cmd,gotoLine[i].flag,line);
        break;
      }
    }
    String_appendChars(&cmd,name);
    FS_shellmode(STDCHANNEL);
    switch (pid=vfork())
    {
      case -1:
      {
        unlink(name);
        FS_fsmode(STDCHANNEL);
        return Value_new_ERROR(value,FORKFAILED,strerror(errno));
      }
      case 0:
      {
        execl(shell,shell,"-c",cmd.character,(const char*)0);
        exit(127);
      }
      default:
      {
        pid_t r;

        while ((r=wait((int*)0))!=-1 && r!=pid);
      }
    }
    FS_fsmode(STDCHANNEL);
    String_destroy(&cmd);
    if ((chn=FS_openin(name))==-1)
    {
      pc=statementpc;
      return Value_new_ERROR(value,IOERROROPEN,name,FS_errmsg);
    }
    Program_new(&newProgram);
    if (Program_merge(&newProgram,chn,value))
    {
      FS_close(chn);
      unlink(name);
      pc=statementpc;
      return value;
    }
    FS_close(chn);
    Program_setname(&newProgram,program.name.character);
    Program_destroy(&program);
    program=newProgram;
    unlink(name);
  }
  return (struct Value*)0;
#else
  return Value_new_ERROR(value,FORKFAILED,strerror(ENOSYS));
#endif
}

struct Value *stmt_ELSE_ELSEIFELSE(struct Value *value)
{
  if (pass==INTERPRET)
  {
    pc=pc.token->u.endifpc;
  }
  if (pass==DECLARE || pass==COMPILE)
  {
    struct Pc elsepc=pc;
    struct Pc *ifinstr;
    int elseifelse=(pc.token->type==T_ELSEIFELSE);

    if ((ifinstr=popLabel(L_IF))==(struct Pc*)0) return Value_new_ERROR(value,STRAYELSE1);
    if (ifinstr->token->type==T_ELSEIFIF) (ifinstr->token-1)->u.elsepc=pc;
    ++pc.token;
    ifinstr->token->u.elsepc=pc;
    assert(ifinstr->token->type==T_ELSEIFIF || ifinstr->token->type==T_IF);
    if (elseifelse) return &more_statements;
    else pushLabel(L_ELSE,&elsepc);
  }
  return (struct Value*)0;
}

struct Value *stmt_END(struct Value *value)
{
  if (pass==INTERPRET)
  {
    pc=pc.token->u.endpc;
    bas_end=1;
  }
  if (pass==DECLARE || pass==COMPILE)
  {
    if (Program_end(&program,&pc.token->u.endpc)) ++pc.token;
    else
    {
      struct Token *eol;

      for (eol=pc.token; eol->type!=T_EOL; ++eol);

      pc.token->u.endpc=pc;
      pc.token->u.endpc.token=eol;
      ++pc.token;
    }
#if 0
    else return Value_new_ERROR(value,NOPROGRAM);
#endif
  }
  return (struct Value*)0;
}

struct Value *stmt_ENDIF(struct Value *value)
{
  if (pass==DECLARE || pass==COMPILE)
  {
    struct Pc endifpc=pc;
    struct Pc *ifpc;
    struct Pc *elsepc;

    if ((ifpc=popLabel(L_IF)))
    {
      ifpc->token->u.elsepc=endifpc;
      if (ifpc->token->type==T_ELSEIFIF) (ifpc->token-1)->u.elsepc=pc;
    }
    else if ((elsepc=popLabel(L_ELSE))) elsepc->token->u.endifpc=endifpc;
    else return Value_new_ERROR(value,STRAYENDIF);
  }
  ++pc.token;
  return (struct Value*)0;
}

struct Value *stmt_ENDFN(struct Value *value)
{
  struct Pc *curfn=(struct Pc*)0;
  struct Pc eqpc=pc;

  if (pass==DECLARE || pass==COMPILE)
  {
    if ((curfn=popLabel(L_FUNC))==(struct Pc*)0) return Value_new_ERROR(value,STRAYENDFN);
    if ((eqpc.token->u.type=(curfn->token+1)->u.identifier->defaultType)==V_VOID) return Value_new_ERROR(value,STRAYENDFN);
  }
  ++pc.token;
  if (pass==INTERPRET) return Value_clone(value,Var_value(Auto_local(&stack,0),0,(int*)0,(struct Value*)0));
  else
  {
    if (pass==DECLARE) Global_endfunction(&globals,(curfn->token+1)->u.identifier,&pc);
    Auto_funcEnd(&stack);
  }
  return (struct Value*)0;
}

struct Value *stmt_ENDPROC_SUBEND(struct Value *value)
{
  struct Pc *curfn=(struct Pc*)0;

  if (pass==DECLARE || pass==COMPILE)
  {
    if ((curfn=popLabel(L_FUNC))==(struct Pc*)0 || (curfn->token+1)->u.identifier->defaultType!=V_VOID)
    {
      if (curfn!=(struct Pc*)0) pushLabel(L_FUNC,curfn);
      return Value_new_ERROR(value,STRAYSUBEND,topLabelDescription());
    }
  }
  ++pc.token;
  if (pass==INTERPRET) return Value_new_VOID(value);
  else
  {
    if (pass==DECLARE) Global_endfunction(&globals,(curfn->token+1)->u.identifier,&pc);
    Auto_funcEnd(&stack);
  }
  return (struct Value*)0;
}

struct Value *stmt_ENDSELECT(struct Value *value)
{
  struct Pc statementpc=pc;

  ++pc.token;
  if (pass==DECLARE || pass==COMPILE)
  {
    struct Pc *selectcasepc;

    if ((selectcasepc=popLabel(L_SELECTCASE))) selectcasepc->token->u.selectcase->endselect=pc;
    else
    {
      pc=statementpc;
      return Value_new_ERROR(value,STRAYENDSELECT);
    }
  }
  return (struct Value*)0;
}

struct Value *stmt_ENVIRON(struct Value *value)
{
  struct Pc epc=pc;

  ++pc.token;
  if (eval(value,_("environment variable"))->type==V_ERROR || Value_retype(value,V_STRING)->type==V_ERROR) return value;
  if (pass==INTERPRET && value->u.string.character)
  {
    if (putenv(value->u.string.character)==-1)
    {
      Value_destroy(value);
      pc=epc;
      return Value_new_ERROR(value,ENVIRONFAILED,strerror(errno));
    }
  }
  Value_destroy(value);
  return (struct Value*)0;
}

struct Value *stmt_FNEXIT(struct Value *value)
{
  struct Pc *curfn=(struct Pc*)0;

  if (pass==DECLARE || pass==COMPILE)
  {
    if ((curfn=findLabel(L_FUNC))==(struct Pc*)0 || (curfn->token+1)->u.identifier->defaultType==V_VOID)
    {
      return Value_new_ERROR(value,STRAYFNEXIT);
    }
  }
  ++pc.token;
  if (pass==INTERPRET) return Value_clone(value,Var_value(Auto_local(&stack,0),0,(int*)0,(struct Value*)0));
  return (struct Value*)0;
}

struct Value *stmt_COLON_EOL(struct Value *value)
{
  return (struct Value*)0;
}

struct Value *stmt_QUOTE_REM(struct Value *value)
{
  ++pc.token;
  return (struct Value*)0;
}

struct Value *stmt_EQ_FNRETURN_FNEND(struct Value *value)
{
  struct Pc *curfn=(struct Pc*)0;
  struct Pc eqpc=pc;
  enum TokenType t=pc.token->type;

  if (pass==DECLARE || pass==COMPILE)
  {
    if (t==T_EQ)
    {
      if ((curfn=popLabel(L_FUNC))==(struct Pc*)0) return Value_new_ERROR(value,STRAYENDEQ);
      if ((eqpc.token->u.type=(curfn->token+1)->u.identifier->defaultType)==V_VOID) return Value_new_ERROR(value,STRAYENDEQ);
    }
    else if (t==T_FNEND)
    {
      if ((curfn=popLabel(L_FUNC))==(struct Pc*)0) return Value_new_ERROR(value,STRAYENDFN);
      if ((eqpc.token->u.type=(curfn->token+1)->u.identifier->defaultType)==V_VOID) return Value_new_ERROR(value,STRAYENDFN);
    }
    else
    {
      if ((curfn=findLabel(L_FUNC))==(struct Pc*)0) return Value_new_ERROR(value,STRAYFNRETURN);
      if ((eqpc.token->u.type=(curfn->token+1)->u.identifier->defaultType)==V_VOID) return Value_new_ERROR(value,STRAYFNRETURN);
    }
  }
  ++pc.token;
  if (eval(value,_("return"))->type==V_ERROR || Value_retype(value,eqpc.token->u.type)->type==V_ERROR)
  {
    if (pass!=INTERPRET) Auto_funcEnd(&stack);
    pc=eqpc;
    return value;
  }
  if (pass==INTERPRET) return value;
  else
  {
    Value_destroy(value);
    if (t==T_EQ || t==T_FNEND)
    {
      if (pass==DECLARE) Global_endfunction(&globals,(curfn->token+1)->u.identifier,&pc);
      Auto_funcEnd(&stack);
    }
  }
  return (struct Value*)0;
}

struct Value *stmt_ERASE(struct Value *value)
{
  ++pc.token;
  while (1)
  {
    if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGARRIDENT);
    if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,GLOBALARRAY,0)==0)
    {
      return Value_new_ERROR(value,REDECLARATION);
    }
    if (pass==INTERPRET)
    {
      Var_destroy(&pc.token->u.identifier->sym->u.var);
    }
    ++pc.token;
    if (pc.token->type==T_COMMA) ++pc.token;
    else break;
  }
  return (struct Value*)0;
}

struct Value *stmt_EXITDO(struct Value *value)
{
  if (pass==INTERPRET) pc=pc.token->u.exitdo;
  else
  {
    if (pass==COMPILE)
    {
      struct Pc *exitdo;

      if ((exitdo=findLabel(L_DO))==(struct Pc*)0 && (exitdo=findLabel(L_DOcondition))==(struct Pc*)0) return Value_new_ERROR(value,STRAYEXITDO);
      pc.token->u.exitdo=exitdo->token->u.exitdo;
    }
    ++pc.token;
  }
  return (struct Value*)0;
}

struct Value *stmt_EXITFOR(struct Value *value)
{
  if (pass==INTERPRET) pc=pc.token->u.exitfor;
  else
  {
    if (pass==COMPILE)
    {
      struct Pc *exitfor;

      if ((exitfor=findLabel(L_FOR))==(struct Pc*)0) return Value_new_ERROR(value,STRAYEXITFOR);
      pc.token->u.exitfor=exitfor->token->u.exitfor;
    }
    ++pc.token;
  }
  return (struct Value*)0;
}

struct Value *stmt_FIELD(struct Value *value)
{
  long int chn,offset,recLength=-1;

  ++pc.token;
  if (pc.token->type==T_CHANNEL) ++pc.token;
  if (eval(value,_("channel"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
  chn=value->u.integer;
  Value_destroy(value);
  if (pass==INTERPRET && (recLength=FS_recLength(chn))==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
  if (pc.token->type!=T_COMMA) return Value_new_ERROR(value,MISSINGCOMMA);
  ++pc.token;
  offset=0;
  while (1)
  {
    struct Pc curpc;
    struct Value *l;
    long int width;

    curpc=pc;
    if (eval(value,_("field width"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
    width=value->u.integer;
    Value_destroy(value);
    if (pass==INTERPRET && offset+width>recLength)
    {
      pc=curpc;
      return Value_new_ERROR(value,OUTOFRANGE,_("field width"));
    }
    if (pc.token->type!=T_AS) return Value_new_ERROR(value,MISSINGAS);
    ++pc.token;
    curpc=pc;
    if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGVARIDENT);
    if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,(pc.token+1)->type==T_OP?GLOBALARRAY:GLOBALVAR,0)==0)
    {
      return Value_new_ERROR(value,REDECLARATION);
    }
    if ((l=lvalue(value))->type==V_ERROR) return value;
    if (pass!=DECLARE && l->type!=V_STRING)
    {
      pc=curpc;
      return Value_new_ERROR(value,TYPEMISMATCH4);
    }
    if (pass==INTERPRET) FS_field(chn,&l->u.string,offset,width);
    offset+=width;
    if (pc.token->type==T_COMMA) ++pc.token;
    else break;
  }
  return (struct Value*)0;
}

struct Value *stmt_FOR(struct Value *value)
{
  struct Pc forpc=pc;
  struct Pc varpc;
  struct Pc limitpc;
  struct Value limit,stepValue;

  ++pc.token;
  varpc=pc;
  if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGLOOPIDENT);
  if (assign(value)->type==V_ERROR) return value;
  if (pass==INTERPRET)
  {
    ++pc.token;
    if (eval(&limit,(const char*)0)->type==V_ERROR)
    {
      *value=limit;
      return value;
    }
    Value_retype(&limit,value->type);
    assert(limit.type!=V_ERROR);
    if (pc.token->type==T_STEP) /* STEP x */
    {
      struct Pc stepPc;

      ++pc.token;
      stepPc=pc;
      if (eval(&stepValue,"`step'")->type==V_ERROR)
      {
        Value_destroy(value);
        *value=stepValue;
        pc=stepPc;
        return value;
      }
      Value_retype(&stepValue,value->type);
      assert(stepValue.type!=V_ERROR);
    }

    else /* implicit numeric STEP */
    {
      if (value->type==V_INTEGER) VALUE_NEW_INTEGER(&stepValue,1);
      else VALUE_NEW_REAL(&stepValue,1.0);
    }

    if (Value_exitFor(value,&limit,&stepValue)) pc=forpc.token->u.exitfor;
    Value_destroy(&limit);
    Value_destroy(&stepValue);
    Value_destroy(value);
  }
  else
  {
    pushLabel(L_FOR,&forpc);
    pushLabel(L_FOR_VAR,&varpc);
    if (pc.token->type!=T_TO)
    {
      Value_destroy(value);
      return Value_new_ERROR(value,MISSINGTO);
    }
    ++pc.token;
    pushLabel(L_FOR_LIMIT,&pc);
    limitpc=pc;
    if (eval(&limit,(const char*)0)==(struct Value*)0)
    {
      Value_destroy(value);
      return Value_new_ERROR(value,MISSINGEXPR,"`to'");
    }
    if (limit.type==V_ERROR)
    {
      Value_destroy(value);
      *value=limit;
      return value;
    }
    if (pass!=DECLARE)
    {
      struct Symbol *sym=varpc.token->u.identifier->sym;

      if (VALUE_RETYPE(&limit,sym->type==GLOBALVAR || sym->type==GLOBALARRAY ? sym->u.var.type : Auto_varType(&stack,sym))->type==V_ERROR)
      {
        Value_destroy(value);
        *value=limit;
        pc=limitpc;
        return value;
      }
    }
    Value_destroy(&limit);
    if (pc.token->type==T_STEP) /* STEP x */
    {
      struct Pc stepPc;

      ++pc.token;
      stepPc=pc;
      if (eval(&stepValue,"`step'")->type==V_ERROR || (pass!=DECLARE && Value_retype(&stepValue,value->type)->type==V_ERROR))
      {
        Value_destroy(value);
        *value=stepValue;
        pc=stepPc;
        return value;
      }
    }

    else /* implicit numeric STEP */
    {
      VALUE_NEW_INTEGER(&stepValue,1);
      if (pass!=DECLARE && VALUE_RETYPE(&stepValue,value->type)->type==V_ERROR)
      {
        Value_destroy(value);
        *value=stepValue;
        Value_errorPrefix(value,_("implicit STEP 1:"));
        return value;
      }
    }

    pushLabel(L_FOR_BODY,&pc);
    Value_destroy(&stepValue);
    Value_destroy(value);
  }
  return (struct Value*)0;
}

struct Value *stmt_GET_PUT(struct Value *value)
{
  struct Pc statementpc=pc;
  int put=pc.token->type==T_PUT;
  long int chn;
  struct Pc errpc;

  ++pc.token;
  if (pc.token->type==T_CHANNEL) ++pc.token;
  if (eval(value,_("channel"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
  chn=value->u.integer;
  Value_destroy(value);
  if (pc.token->type==T_COMMA)
  {
    ++pc.token;
    errpc=pc;
    if (eval(value,(const char*)0)) /* process record number/position */
    {
      int rec;

      if (value->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
      rec=value->u.integer;
      Value_destroy(value);
      if (pass==INTERPRET)
      {
        if (rec<1)
        {
          pc=errpc;
          return Value_new_ERROR(value,OUTOFRANGE,_("record number"));
        }
        if (FS_seek((int)chn,rec-1)==-1)
        {
          pc=statementpc;
          return Value_new_ERROR(value,IOERROR,FS_errmsg);
        }
      }
    }

  }
  if (pc.token->type==T_COMMA) /* BINARY mode get/put */
  {
    int res=-1;

    ++pc.token;
    if (put)
    {
      if (eval(value,_("`put'/`get' data"))->type==V_ERROR) return value;
      if (pass==INTERPRET)
      {
        switch (value->type)
        {
          case V_INTEGER: res=FS_putbinaryInteger(chn,value->u.integer); break;
          case V_REAL: res=FS_putbinaryReal(chn,value->u.real); break;
          case V_STRING: res=FS_putbinaryString(chn,&value->u.string); break;
          default: assert(0);
        }
      }
      Value_destroy(value);
    }
    else
    {
      struct Value *l;

      if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGPROCIDENT);
      if (pass==DECLARE)
      {
        if
        (
          ((pc.token+1)->type==T_OP || Auto_find(&stack,pc.token->u.identifier)==0)
          && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,(pc.token+1)->type==T_OP?GLOBALARRAY:GLOBALVAR,0)==0
        )
        {
          return Value_new_ERROR(value,REDECLARATION);
        }
      }
      if ((l=lvalue(value))->type==V_ERROR) return value;
      if (pass==INTERPRET)
      {
        switch (l->type)
        {
          case V_INTEGER: res=FS_getbinaryInteger(chn,&l->u.integer); break;
          case V_REAL: res=FS_getbinaryReal(chn,&l->u.real); break;
          case V_STRING: res=FS_getbinaryString(chn,&l->u.string); break;
          default: assert(0);
        }
      }
    }
    if (pass==INTERPRET && res==-1)
    {
      pc=statementpc;
      return Value_new_ERROR(value,IOERROR,FS_errmsg);
    }
  }

  else if (pass==INTERPRET && ((put ? FS_put : FS_get)(chn))==-1)
  {
    pc=statementpc;
    return Value_new_ERROR(value,IOERROR,FS_errmsg);
  }
  return (struct Value*)0;
}

struct Value *stmt_GOSUB(struct Value *value)
{
  if (pass==INTERPRET)
  {
    if (!program.runnable && compileProgram(value,!DIRECTMODE)->type==V_ERROR) return value;
    pc.token+=2;
    Auto_pushGosubRet(&stack,&pc);
    pc=(pc.token-2)->u.gosubpc;
    Program_trace(&program,&pc,0,1);
  }
  if (pass==DECLARE || pass==COMPILE)
  {
    struct Token *gosubpc=pc.token;

    ++pc.token;
    if (pc.token->type!=T_INTEGER) return Value_new_ERROR(value,MISSINGLINENUMBER);
    if (Program_goLine(&program,pc.token->u.integer,&gosubpc->u.gosubpc)==(struct Pc*)0) return Value_new_ERROR(value,NOSUCHLINE);
    if (pass==COMPILE && Program_scopeCheck(&program,&gosubpc->u.gosubpc,findLabel(L_FUNC))) return Value_new_ERROR(value,OUTOFSCOPE);
    ++pc.token;
  }
  return (struct Value*)0;
}

struct Value *stmt_RESUME_GOTO(struct Value *value)
{
  if (pass==INTERPRET)
  {
    if (!program.runnable && compileProgram(value,!DIRECTMODE)->type==V_ERROR) return value;
    if (pc.token->type==T_RESUME)
    {
      if (!stack.resumeable) return Value_new_ERROR(value,STRAYRESUME);
      stack.resumeable=0;
    }
    pc=pc.token->u.gotopc;
    Program_trace(&program,&pc,0,1);
  }
  else if (pass==DECLARE || pass==COMPILE)
  {
    struct Token *gotopc=pc.token;

    ++pc.token;
    if (pc.token->type!=T_INTEGER) return Value_new_ERROR(value,MISSINGLINENUMBER);
    if (Program_goLine(&program,pc.token->u.integer,&gotopc->u.gotopc)==(struct Pc*)0) return Value_new_ERROR(value,NOSUCHLINE);
    if (pass==COMPILE && Program_scopeCheck(&program,&gotopc->u.gotopc,findLabel(L_FUNC))) return Value_new_ERROR(value,OUTOFSCOPE);
    ++pc.token;
  }
  return (struct Value*)0;
}

struct Value *stmt_KILL(struct Value *value)
{
  struct Pc statementpc=pc;

  ++pc.token;
  if (eval(value,_("file name"))->type==V_ERROR || (pass!=DECLARE && Value_retype(value,V_STRING)->type==V_ERROR)) return value;
  if (pass==INTERPRET && unlink(value->u.string.character)==-1)
  {
    const char *msg=strerror(errno);

    Value_destroy(value);
    pc=statementpc;
    return Value_new_ERROR(value,IOERROR,msg);
  }
  else Value_destroy(value);
  return (struct Value*)0;
}

struct Value *stmt_LET(struct Value *value)
{
  ++pc.token;
  if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGVARIDENT);
  if (assign(value)->type==V_ERROR) return value;
  if (pass!=INTERPRET) Value_destroy(value);
  return (struct Value*)0;
}

struct Value *stmt_LINEINPUT(struct Value *value)
{
  int channel=0;
  struct Pc lpc;
  struct Value *l;

  ++pc.token;
  if (pc.token->type==T_CHANNEL)
  {
    ++pc.token;
    if (eval(value,_("channel"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
    channel=value->u.integer;
    Value_destroy(value);
    if (pc.token->type!=T_COMMA) return Value_new_ERROR(value,MISSINGCOMMA);
    else ++pc.token;
  }

  /* prompt */
  if (pc.token->type==T_STRING)
  {
    if (pass==INTERPRET && channel==0) FS_putString(channel,pc.token->u.string);
    ++pc.token;
    if (pc.token->type!=T_SEMICOLON && pc.token->type!=T_COMMA) return Value_new_ERROR(value,MISSINGSEMICOMMA);
    ++pc.token;
  }
  if (pass==INTERPRET && channel==0) FS_flush(channel);

  if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGVARIDENT);
  if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,(pc.token+1)->type==T_OP?GLOBALARRAY:GLOBALVAR,0)==0)
  {
    return Value_new_ERROR(value,REDECLARATION);
  }
  lpc=pc;
  if (((l=lvalue(value))->type)==V_ERROR) return value;
  if (pass==COMPILE && l->type!=V_STRING)
  {
    pc=lpc;
    return Value_new_ERROR(value,TYPEMISMATCH4);
  }
  if (pass==INTERPRET)
  {
    String_size(&l->u.string,0);
    if (FS_appendToString(channel,&l->u.string,1)==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
    if (l->u.string.length==0) return Value_new_ERROR(value,IOERROR,_("end of file"));
    if (l->u.string.character[l->u.string.length-1]=='\n')
    {
      String_size(&l->u.string,l->u.string.length-1);
    }
  }
  return (struct Value*)0;
}

struct Value *stmt_LIST_LLIST(struct Value *value)
{
  struct Pc from,to;
  int f=0,t=0,channel;

  channel=(pc.token->type==T_LLIST?LPCHANNEL:STDCHANNEL);
  ++pc.token;
  if (pc.token->type==T_INTEGER)
  {
    if (pass==INTERPRET && Program_fromLine(&program,pc.token->u.integer,&from)==(struct Pc*)0) return Value_new_ERROR(value,NOSUCHLINE);
    f=1;
    ++pc.token;
  }
  else if (pc.token->type!=T_MINUS && pc.token->type!=T_COMMA)
  {
    if (eval(value,(const char*)0))
    {
      if (value->type==V_ERROR || (pass!=DECLARE && Value_retype(value,V_INTEGER)->type==V_ERROR)) return value;
      if (pass==INTERPRET && Program_fromLine(&program,value->u.integer,&from)==(struct Pc*)0) return Value_new_ERROR(value,NOSUCHLINE);
      f=1;
      Value_destroy(value);
    }
  }
  if (pc.token->type==T_MINUS || pc.token->type==T_COMMA)
  {
    ++pc.token;
    if (eval(value,(const char*)0))
    {
      if (value->type==V_ERROR || (pass!=DECLARE && Value_retype(value,V_INTEGER)->type==V_ERROR)) return value;
      if (pass==INTERPRET && Program_toLine(&program,value->u.integer,&to)==(struct Pc*)0) return Value_new_ERROR(value,NOSUCHLINE);
      t=1;
      Value_destroy(value);
    }
  }
  else if (f==1)
  {
    to=from;
    t=1;
  }
  if (pass==INTERPRET)
  {
    /* Some implementations do not require direct mode */
    if (Program_list(&program,channel,channel==STDCHANNEL,f?&from:(struct Pc*)0,t?&to:(struct Pc*)0,value)) return value;
  }
  return (struct Value*)0;
}

struct Value *stmt_LOAD(struct Value *value)
{
  struct Pc loadpc;

  if (pass==INTERPRET && !DIRECTMODE) return Value_new_ERROR(value,NOTINPROGRAMMODE);
  ++pc.token;
  loadpc=pc;
  if (eval(value,_("file name"))->type==V_ERROR || Value_retype(value,V_STRING)->type==V_ERROR)
  {
    pc=loadpc;
    return value;
  }
  if (pass==INTERPRET)
  {
    int dev;

    new();
    Program_setname(&program,value->u.string.character);
    if ((dev=FS_openin(value->u.string.character))==-1)
    {
      pc=loadpc;
      Value_destroy(value);
      return Value_new_ERROR(value,IOERROR,FS_errmsg);
    }
    FS_width(dev,0);
    Value_destroy(value);
    if (Program_merge(&program,dev,value))
    {
      pc=loadpc;
      return value;
    }
    FS_close(dev);
    program.unsaved=0;
  }
  else Value_destroy(value);
  return (struct Value*)0;
}

struct Value *stmt_LOCAL(struct Value *value)
{
  struct Pc *curfn=(struct Pc*)0;

  if (pass==DECLARE || pass==COMPILE)
  {
    if ((curfn=findLabel(L_FUNC))==(struct Pc*)0) return Value_new_ERROR(value,STRAYLOCAL);
  }
  ++pc.token;
  while (1)
  {
    if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGVARIDENT);
    if (pass==DECLARE || pass==COMPILE)
    {
      struct Symbol *fnsym;

      if (Auto_variable(&stack,pc.token->u.identifier)==0) return Value_new_ERROR(value,ALREADYLOCAL);
      if (pass==DECLARE)
      {
        assert(curfn->token->type==T_DEFFN || curfn->token->type==T_DEFPROC || curfn->token->type==T_SUB || curfn->token->type==T_FUNCTION);
        fnsym=(curfn->token+1)->u.identifier->sym;
        assert(fnsym);
        fnsym->u.sub.u.def.localTypes=realloc(fnsym->u.sub.u.def.localTypes,sizeof(enum ValueType)*(fnsym->u.sub.u.def.localLength+1));
        fnsym->u.sub.u.def.localTypes[fnsym->u.sub.u.def.localLength]=pc.token->u.identifier->defaultType;
        ++fnsym->u.sub.u.def.localLength;
      }
    }
    ++pc.token;
    if (pc.token->type==T_COMMA) ++pc.token;
    else break;
  }
  return (struct Value*)0;
}

struct Value *stmt_LOCATE(struct Value *value)
{
  long int line,column;
  struct Pc argpc;
  struct Pc statementpc=pc;

  ++pc.token;
  argpc=pc;
  if (eval(value,_("row"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
  line=value->u.integer;
  Value_destroy(value);
  if (pass==INTERPRET && line<1)
  {
    pc=argpc;
    return Value_new_ERROR(value,OUTOFRANGE,_("row"));
  }
  if (pc.token->type==T_COMMA) ++pc.token;
  else return Value_new_ERROR(value,MISSINGCOMMA);
  argpc=pc;
  if (eval(value,_("column"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
  column=value->u.integer;
  Value_destroy(value);
  if (pass==INTERPRET && column<1)
  {
    pc=argpc;
    return Value_new_ERROR(value,OUTOFRANGE,_("column"));
  }
  if (pass==INTERPRET && FS_locate(STDCHANNEL,line,column)==-1)
  {
    pc=statementpc;
    return Value_new_ERROR(value,IOERROR,FS_errmsg);
  }
  return (struct Value*)0;
}

struct Value *stmt_LOCK_UNLOCK(struct Value *value)
{
  int lock=pc.token->type==T_LOCK;
  int channel;

  ++pc.token;
  if (pc.token->type==T_CHANNEL) ++pc.token;
  if (eval(value,_("channel"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
  channel=value->u.integer;
  Value_destroy(value);
  if (pass==INTERPRET)
  {
    if (FS_lock(channel,0,0,lock?FS_LOCK_EXCLUSIVE:FS_LOCK_NONE,1)==-1)
    {
      return Value_new_ERROR(value,IOERROR,FS_errmsg);
    }
  }
  return (struct Value*)0;
}

struct Value *stmt_LOOP(struct Value *value)
{
  struct Pc looppc=pc;
  struct Pc *dopc;

  ++pc.token;
  if (pass==INTERPRET)
  {
    pc=looppc.token->u.dopc;
  }
  if (pass==DECLARE || pass==COMPILE)
  {
    if ((dopc=popLabel(L_DO))==(struct Pc*)0 && (dopc=popLabel(L_DOcondition))==(struct Pc*)0) return Value_new_ERROR(value,STRAYLOOP);
    looppc.token->u.dopc=*dopc;
    dopc->token->u.exitdo=pc;
  }
  return (struct Value*)0;
}

struct Value *stmt_LOOPUNTIL(struct Value *value)
{
  struct Pc loopuntilpc=pc;
  struct Pc *dopc;

  ++pc.token;
  if (eval(value,_("condition"))->type==V_ERROR) return value;
  if (pass==INTERPRET)
  {
    if (Value_isNull(value)) pc=loopuntilpc.token->u.dopc;
    Value_destroy(value);
  }
  if (pass==DECLARE || pass==COMPILE)
  {
    if ((dopc=popLabel(L_DO))==(struct Pc*)0) return Value_new_ERROR(value,STRAYLOOPUNTIL);
    loopuntilpc.token->u.until=*dopc;
    dopc->token->u.exitdo=pc;
  }
  return (struct Value*)0;
}

struct Value *stmt_LSET_RSET(struct Value *value)
{
  struct Value *l;
  struct Pc tmppc;
  int lset=(pc.token->type==T_LSET);

  ++pc.token;
  if (pass==DECLARE)
  {
    if
    (
      ((pc.token+1)->type==T_OP || Auto_find(&stack,pc.token->u.identifier)==0)
      && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,(pc.token+1)->type==T_OP?GLOBALARRAY:GLOBALVAR,0)==0
    )
    {
      return Value_new_ERROR(value,REDECLARATION);
    }
  }
  tmppc=pc;
  if ((l=lvalue(value))->type==V_ERROR) return value;
  if (pass==COMPILE && l->type!=V_STRING)
  {
    pc=tmppc;
    return Value_new_ERROR(value,TYPEMISMATCH4);
  }
  if (pc.token->type!=T_EQ) return Value_new_ERROR(value,MISSINGEQ);
  ++pc.token;
  tmppc=pc;
  if (eval(value,_("rhs"))->type==V_ERROR || (pass!=DECLARE && Value_retype(value,l->type)->type==V_ERROR))
  {
    pc=tmppc;
    return value;
  }
  if (pass==INTERPRET) (lset ? String_lset : String_rset)(&l->u.string,&value->u.string);
  Value_destroy(value);
  return (struct Value*)0;
}

struct Value *stmt_IDENTIFIER(struct Value *value)
{
  struct Pc here=pc;

  if (pass==DECLARE)
  {
    if (func(value)->type==V_ERROR) return value;
    else Value_destroy(value);
    if (pc.token->type==T_EQ || pc.token->type==T_COMMA)
    {
      pc=here;
      if (assign(value)->type==V_ERROR) return value;
      Value_destroy(value);
    }
  }
  else
  {
    if (pass==COMPILE)
    {
      if
      (
        ((pc.token+1)->type==T_OP || Auto_find(&stack,pc.token->u.identifier)==0)
        && Global_find(&globals,pc.token->u.identifier,(pc.token+1)->type==T_OP)==0
      ) return Value_new_ERROR(value,UNDECLARED);
    }
    if (strcasecmp(pc.token->u.identifier->name,"mid$")
        && (pc.token->u.identifier->sym->type==USERFUNCTION || pc.token->u.identifier->sym->type==BUILTINFUNCTION))
    {
      func(value);
      if (Value_retype(value,V_VOID)->type==V_ERROR) return value;
      Value_destroy(value);
    }
    else
    {
      if (assign(value)->type==V_ERROR) return value;
      if (pass!=INTERPRET) Value_destroy(value);
    }
  }

  return (struct Value*)0;
}

struct Value *stmt_IF_ELSEIFIF(struct Value *value)
{
  struct Pc ifpc=pc;

  ++pc.token;
  if (eval(value,_("condition"))->type==V_ERROR) return value;
  if (pc.token->type!=T_THEN)
  {
    Value_destroy(value);
    return Value_new_ERROR(value,MISSINGTHEN);
  }
  ++pc.token;
  if (pass==INTERPRET)
  {
    if (Value_isNull(value)) pc=ifpc.token->u.elsepc;
    Value_destroy(value);
  }
  else
  {
    Value_destroy(value);
    if (pc.token->type==T_EOL)
    {
      pushLabel(L_IF,&ifpc);
    }
    else /* compile single line IF THEN ELSE recursively */
    {
      if (statements(value)->type==V_ERROR) return value;
      Value_destroy(value);
      if (pc.token->type==T_ELSE)
      {
        struct Pc elsepc=pc;

        ++pc.token;
        ifpc.token->u.elsepc=pc;
        if (ifpc.token->type==T_ELSEIFIF) (ifpc.token-1)->u.elsepc=pc;
        if (statements(value)->type==V_ERROR) return value;
        Value_destroy(value);
        elsepc.token->u.endifpc=pc;
      }
      else
      {
        ifpc.token->u.elsepc=pc;
        if (ifpc.token->type==T_ELSEIFIF) (ifpc.token-1)->u.elsepc=pc;
      }
    }

  }
  return (struct Value*)0;
}

struct Value *stmt_IMAGE(struct Value *value)
{
  ++pc.token;
  if (pc.token->type!=T_STRING) return Value_new_ERROR(value,MISSINGFMT);
  ++pc.token;
  return (struct Value*)0;
}

struct Value *stmt_INPUT(struct Value *value)
{
  int channel=STDCHANNEL;
  int nl=1;
  int extraprompt=1;
  struct Token *inputdata=(struct Token*)0,*t=(struct Token*)0;
  struct Pc lvaluepc;

  ++pc.token;
  if (pc.token->type==T_CHANNEL)
  {
    ++pc.token;
    if (eval(value,_("channel"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
    channel=value->u.integer;
    Value_destroy(value);
    if (pc.token->type!=T_COMMA) return Value_new_ERROR(value,MISSINGCOMMA);
    else ++pc.token;
  }

  if (pc.token->type==T_SEMICOLON)
  {
    nl=0;
    ++pc.token;
  }

  /* prompt */
  if (pc.token->type==T_STRING)
  {
    if (pass==INTERPRET && channel==STDCHANNEL) FS_putString(STDCHANNEL,pc.token->u.string);
    ++pc.token;
    if (pc.token->type==T_COMMA || pc.token->type==T_COLON) { ++pc.token; extraprompt=0; }
    else if (pc.token->type==T_SEMICOLON) ++pc.token;
    else extraprompt=0;
  }
  if (pass==INTERPRET && channel==STDCHANNEL && extraprompt)
  {
    FS_putChars(STDCHANNEL,"? ");
  }

  retry:
  if (pass==INTERPRET) /* read input line and tokenise it */
  {
    struct String s;

    if (channel==STDCHANNEL) FS_flush(STDCHANNEL);
    String_new(&s);
    if (FS_appendToString(channel,&s,nl)==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
    if (s.length==0) return Value_new_ERROR(value,IOERROR,_("end of file"));
    inputdata=t=Token_newData(s.character);
    String_destroy(&s);
  }

  while (1)
  {
    struct Value *l;

    if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGVARIDENT);
    if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,(pc.token+1)->type==T_OP?GLOBALARRAY:GLOBALVAR,0)==0)
    {
      return Value_new_ERROR(value,REDECLARATION);
    }
    lvaluepc=pc;
    if (((l=lvalue(value))->type)==V_ERROR) return value;
    if (pass==INTERPRET)
    {
      if (t->type==T_COMMA || t->type==T_EOL)
      {
        enum ValueType ltype=l->type;

        Value_destroy(l);
        Value_new_null(l,ltype);
      }
      else if (convert(value,l,t))
      {
        pc=lvaluepc;
        if (channel==STDCHANNEL)
        {
          struct String s;

          String_new(&s);
          Value_toString(value,&s,' ',-1,0,0,0,0,-1,0,0);
          String_appendChars(&s," ?? ");
          FS_putString(STDCHANNEL,&s);
          String_destroy(&s);
          Value_destroy(value);
          Token_destroy(inputdata);
          goto retry;
        }
        else
        {
          Token_destroy(inputdata);
          return value;
        }
      }
      else ++t;
      if (pc.token->type==T_COMMA)
      {
        if (t->type==T_COMMA) ++t;
        else
        {
          Token_destroy(inputdata);
          if (channel==STDCHANNEL)
          {
            FS_putChars(STDCHANNEL,"?? ");
            ++pc.token;
            goto retry;
          }
          else
          {
            pc=lvaluepc;
            return Value_new_ERROR(value,MISSINGINPUTDATA);
          }
        }
      }
    }
    if (pc.token->type==T_COMMA) ++pc.token;
    else break;
  }
  if (pass==INTERPRET)
  {
    if (t->type!=T_EOL) FS_putChars(STDCHANNEL,_("Too much input data\n"));
    Token_destroy(inputdata);
  }
  return (struct Value*)0;
}

struct Value *stmt_MAT(struct Value *value)
{
  struct Var *var1,*var2,*var3=(struct Var*)0;
  struct Pc oppc;
  enum TokenType op=T_EOL;

  oppc.line=-1;
  oppc.token=(struct Token*)0;
  ++pc.token;
  if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGMATIDENT);
  if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,GLOBALARRAY,0)==0)
  {
    return Value_new_ERROR(value,REDECLARATION);
  }
  var1=&pc.token->u.identifier->sym->u.var;
  ++pc.token;
  if (pc.token->type!=T_EQ) return Value_new_ERROR(value,MISSINGEQ);
  ++pc.token;
  if (pc.token->type==T_IDENTIFIER) /* a = b [ +|-|* c ] */
  {
    if (pass==COMPILE)
    {
      if
      (
        ((pc.token+1)->type==T_OP || Auto_find(&stack,pc.token->u.identifier)==0)
        && Global_find(&globals,pc.token->u.identifier,1)==0
      ) return Value_new_ERROR(value,UNDECLARED);
    }
    var2=&pc.token->u.identifier->sym->u.var;
    if (pass==INTERPRET && ((var2->dim!=1 && var2->dim!=2) || var2->base<0 || var2->base>1)) return Value_new_ERROR(value,NOMATRIX,var2->dim,var2->base);
    if (pass==COMPILE && Value_commonType[var1->type][var2->type]==V_ERROR) return Value_new_typeError(value,var2->type,var1->type);
    ++pc.token;
    if (pc.token->type==T_PLUS || pc.token->type==T_MINUS || pc.token->type==T_MULT)
    {
      oppc=pc;
      op=pc.token->type;
      ++pc.token;
      if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGARRIDENT);
      if (pass==COMPILE)
      {
        if
        (
          ((pc.token+1)->type==T_OP || Auto_find(&stack,pc.token->u.identifier)==0)
          && Global_find(&globals,pc.token->u.identifier,1)==0
        ) return Value_new_ERROR(value,UNDECLARED);
      }
      var3=&pc.token->u.identifier->sym->u.var;
      if (pass==INTERPRET && ((var3->dim!=1 && var3->dim!=2) || var3->base<0 || var3->base>1)) return Value_new_ERROR(value,NOMATRIX,var3->dim,var3->base);
      ++pc.token;
    }
    if (pass!=DECLARE)
    {
      if (var3==(struct Var*)0)
      {
        if (Var_mat_assign(var1,var2,value,pass==INTERPRET))
        {
          assert(oppc.line!=-1);
          pc=oppc;
          return value;
        }
      }
      else if (op==T_MULT)
      {
        if (Var_mat_mult(var1,var2,var3,value,pass==INTERPRET))
        {
          assert(oppc.line!=-1);
          pc=oppc;
          return value;
        }
      }
      else if (Var_mat_addsub(var1,var2,var3,op==T_PLUS,value,pass==INTERPRET))
      {
        assert(oppc.line!=-1);
        pc=oppc;
        return value;
      }
    }
  }

  else if (pc.token->type==T_OP)
  {
    if (var1->type==V_STRING) return Value_new_ERROR(value,TYPEMISMATCH5);
    ++pc.token;
    if (eval(value,_("factor"))->type==V_ERROR) return value;
    if (pass==COMPILE && Value_commonType[var1->type][value->type]==V_ERROR) return Value_new_typeError(value,var1->type,value->type);
    if (pc.token->type!=T_CP)
    {
      Value_destroy(value);
      return Value_new_ERROR(value,MISSINGCP);
    }
    ++pc.token;
    if (pc.token->type!=T_MULT)
    {
      Value_destroy(value);
      return Value_new_ERROR(value,MISSINGMULT);
    }
    oppc=pc;
    ++pc.token;
    if (pass==COMPILE)
    {
      if
      (
        ((pc.token+1)->type==T_OP || Auto_find(&stack,pc.token->u.identifier)==0)
        && Global_find(&globals,pc.token->u.identifier,1)==0
      )
      {
        Value_destroy(value);
        return Value_new_ERROR(value,UNDECLARED);
      }
    }
    var2=&pc.token->u.identifier->sym->u.var;
    if (pass==INTERPRET && ((var2->dim!=1 && var2->dim!=2) || var2->base<0 || var2->base>1))
    {
      Value_destroy(value);
      return Value_new_ERROR(value,NOMATRIX,var2->dim,var2->base);
    }
    if (pass!=DECLARE && Var_mat_scalarMult(var1,value,var2,pass==INTERPRET))
    {
      assert(oppc.line!=-1);
      pc=oppc;
      return value;
    }
    Value_destroy(value);
    ++pc.token;
  }

  else if (pc.token->type==T_CON || pc.token->type==T_ZER || pc.token->type==T_IDN)
  {
    op=pc.token->type;
    if (pass==COMPILE && Value_commonType[var1->type][V_INTEGER]==V_ERROR) return Value_new_typeError(value,V_INTEGER,var1->type);
    ++pc.token;
    if (pc.token->type==T_OP)
    {
      unsigned int dim,geometry[2];
      enum ValueType vartype=var1->type;

      ++pc.token;
      if (evalGeometry(value,&dim,geometry)) return value;
      if (pass==INTERPRET)
      {
        Var_destroy(var1);
        Var_new(var1,vartype,dim,geometry,optionbase);
      }
    }
    if (pass==INTERPRET)
    {
      unsigned int i;
      int unused=1-var1->base;

      if ((var1->dim!=1 && var1->dim!=2) || var1->base<0 || var1->base>1) return Value_new_ERROR(value,NOMATRIX,var1->dim,var1->base);
      if (var1->dim==1)
      {
        for (i=unused; i<var1->geometry[0]; ++i)
        {
          int c=-1;

          Value_destroy(&(var1->value[i]));
          switch (op)
          {
            case T_CON: c=1; break;
            case T_ZER: c=0; break;
            case T_IDN: c=(i==unused?1:0); break;
            default: assert(0);
          }
          if (var1->type==V_INTEGER) Value_new_INTEGER(&(var1->value[i]),c);
          else Value_new_REAL(&(var1->value[i]),(double)c);
        }
      }
      else
      {
        int j;

        for (i=unused; i<var1->geometry[0]; ++i) for (j=unused; j<var1->geometry[1]; ++j)
        {
          int c=-1;

          Value_destroy(&(var1->value[i*var1->geometry[1]+j]));
          switch (op)
          {
            case T_CON: c=1; break;
            case T_ZER: c=0; break;
            case T_IDN: c=(i==j?1:0); break;
            default: assert(0);
          }
          if (var1->type==V_INTEGER) Value_new_INTEGER(&(var1->value[i*var1->geometry[1]+j]),c);
          else Value_new_REAL(&(var1->value[i*var1->geometry[1]+j]),(double)c);
        }
      }
    }
  }

  else if (pc.token->type==T_TRN || pc.token->type==T_INV)
  {
    op=pc.token->type;
    ++pc.token;
    if (pc.token->type!=T_OP) return Value_new_ERROR(value,MISSINGOP);
    ++pc.token;
    if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGMATIDENT);
    if (pass==COMPILE)
    {
      if
      (
        ((pc.token+1)->type==T_OP || Auto_find(&stack,pc.token->u.identifier)==0)
        && Global_find(&globals,pc.token->u.identifier,1)==0
      ) return Value_new_ERROR(value,UNDECLARED);
    }
    var2=&pc.token->u.identifier->sym->u.var;
    if (pass==COMPILE && Value_commonType[var1->type][var2->type]==V_ERROR) return Value_new_typeError(value,var2->type,var1->type);
    if (pass==INTERPRET)
    {
      if (var2->dim!=2 || var2->base<0 || var2->base>1) return Value_new_ERROR(value,NOMATRIX,var2->dim,var2->base);
      switch (op)
      {
        case T_TRN: Var_mat_transpose(var1,var2); break;
        case T_INV: if (Var_mat_invert(var1,var2,&stack.lastdet,value)) return value; break;
        default: assert(0);
      }
    }
    ++pc.token;
    if (pc.token->type!=T_CP) return Value_new_ERROR(value,MISSINGCP);
    ++pc.token;
  }

  else return Value_new_ERROR(value,MISSINGEXPR,_("matrix"));
  return (struct Value*)0;
}

struct Value *stmt_MATINPUT(struct Value *value)
{
  int channel=STDCHANNEL;

  ++pc.token;
  if (pc.token->type==T_CHANNEL)
  {
    ++pc.token;
    if (eval(value,_("channel"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
    channel=value->u.integer;
    Value_destroy(value);
    if (pc.token->type!=T_COMMA) return Value_new_ERROR(value,MISSINGCOMMA);
    else ++pc.token;
  }

  while (1)
  {
    struct Pc lvaluepc;
    struct Var *var;

    lvaluepc=pc;
    if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGMATIDENT);
    if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,GLOBALARRAY,0)==0)
    {
      return Value_new_ERROR(value,REDECLARATION);
    }
    var=&pc.token->u.identifier->sym->u.var;
    ++pc.token;
    if (pc.token->type==T_OP)
    {
      unsigned int dim,geometry[2];
      enum ValueType vartype=var->type;

      ++pc.token;
      if (evalGeometry(value,&dim,geometry)) return value;
      if (pass==INTERPRET)
      {
        Var_destroy(var);
        Var_new(var,vartype,dim,geometry,optionbase);
      }
    }
    if (pass==INTERPRET)
    {
      unsigned int i,j;
      int unused=1-var->base;
      int columns;
      struct Token *inputdata,*t;

      if (var->dim!=1 && var->dim!=2) return Value_new_ERROR(value,NOMATRIX,var->dim);
      columns=var->dim==1 ? 0 : var->geometry[1];
      inputdata=t=(struct Token*)0;
      for (i=unused,j=unused; i<var->geometry[0]; )
      {
        struct String s;

        if (!inputdata)
        {
          if (channel==STDCHANNEL)
          {
            FS_putChars(STDCHANNEL,"? ");
            FS_flush(STDCHANNEL);
          }
          String_new(&s);
          if (FS_appendToString(channel,&s,1)==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
          if (s.length==0) return Value_new_ERROR(value,IOERROR,_("end of file"));
          inputdata=t=Token_newData(s.character);
          String_destroy(&s);
        }

        if (t->type==T_COMMA)
        {
          Value_destroy(&(var->value[j*columns+i]));
          Value_new_null(&(var->value[j*columns+i]),var->type);
          ++t;
        }
        else if (t->type==T_EOL)
        {
          while (i<var->geometry[0])
          {
            Value_destroy(&(var->value[j*columns+i]));
            Value_new_null(&(var->value[j*columns+i]),var->type);
            ++i;
          }
        }
        else if (convert(value,&(var->value[j*columns+i]),t))
        {
          Token_destroy(inputdata);
          pc=lvaluepc;
          return value;
        }
        else
        {
          ++t;
          ++i;
          if (t->type==T_COMMA) ++t;
        }

        if (i==var->geometry[0] && j<(columns-1))
        {
          i=unused;
          ++j;
          if (t->type==T_EOL)
          {
            Token_destroy(inputdata);
            inputdata=(struct Token*)0;
          }
        }
      }
    }
    if (pc.token->type==T_COMMA) ++pc.token;
    else break;
  }
  return (struct Value*)0;
}

struct Value *stmt_MATPRINT(struct Value *value)
{
  int chn=STDCHANNEL;
  int printusing=0;
  struct Value usingval;
  struct String *using=(struct String*)0;
  size_t usingpos=0;
  int notfirst=0;

  ++pc.token;
  if (chn==STDCHANNEL && pc.token->type==T_CHANNEL)
  {
    ++pc.token;
    if (eval(value,_("channel"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
    chn=value->u.integer;
    Value_destroy(value);
    if (pc.token->type==T_COMMA) ++pc.token;
  }

  if (pc.token->type==T_USING)
  {
    struct Pc usingpc;

    usingpc=pc;
    printusing=1;
    ++pc.token;
    if (pc.token->type==T_INTEGER)
    {
      if (pass==COMPILE && Program_imageLine(&program,pc.token->u.integer,&usingpc.token->u.image)==(struct Pc*)0) return Value_new_ERROR(value,NOSUCHIMAGELINE);
      else if (pass==INTERPRET) using=usingpc.token->u.image.token->u.string;
      Value_new_STRING(&usingval);
      ++pc.token;
    }
    else
    {
      if (eval(&usingval,_("format string"))->type==V_ERROR || Value_retype(&usingval,V_STRING)->type==V_ERROR)
      {
        *value=usingval;
        return value;
      }
      using=&usingval.u.string;
    }
    if (pc.token->type!=T_SEMICOLON)
    {
      Value_destroy(&usingval);
      return Value_new_ERROR(value,MISSINGSEMICOLON);
    }
    ++pc.token;
  }

  else
  {
    Value_new_STRING(&usingval);
    using=&usingval.u.string;
  }
  while (1)
  {
    struct Var *var;
    int zoned=1;

    if (pc.token->type!=T_IDENTIFIER)
    {
      if (notfirst) break;
      Value_destroy(&usingval);
      return Value_new_ERROR(value,MISSINGMATIDENT);
    }
    if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,GLOBALARRAY,0)==0)
    {
      Value_destroy(&usingval);
      return Value_new_ERROR(value,REDECLARATION);
    }
    var=&pc.token->u.identifier->sym->u.var;
    ++pc.token;
    if (pc.token->type==T_SEMICOLON) zoned=0;
    if (pass==INTERPRET)
    {
      unsigned int i,j;
      int unused=1-var->base;
      int g0,g1;

      if ((var->dim!=1 && var->dim!=2) || var->base<0 || var->base>1) return Value_new_ERROR(value,NOMATRIX,var->dim,var->base);
      if ((notfirst ? FS_putChar(chn,'\n') : FS_nextline(chn))==-1)
      {
        Value_destroy(&usingval);
        return Value_new_ERROR(value,IOERROR,FS_errmsg);
      }
      g0=var->geometry[0];
      g1=var->dim==1 ? unused+1 : var->geometry[1];
      for (i=unused; i<g0; ++i)
      {
        for (j=unused; j<g1; ++j)
        {
          struct String s;

          String_new(&s);
          Value_clone(value,&(var->value[var->dim==1 ? i : i*g1+j]));
          if (Value_toStringUsing(value,&s,using,&usingpos)->type==V_ERROR)
          {
            Value_destroy(&usingval);
            String_destroy(&s);
            return value;
          }
          Value_destroy(value);
          if (FS_putString(chn,&s)==-1)
          {
            Value_destroy(&usingval);
            String_destroy(&s);
            return Value_new_ERROR(value,IOERROR,FS_errmsg);
          }
          String_destroy(&s);
          if (!printusing && zoned) FS_nextcol(chn);
        }
        if (FS_putChar(chn,'\n')==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
      }
    }
    if (pc.token->type==T_COMMA || pc.token->type==T_SEMICOLON) ++pc.token;
    else break;
    notfirst=1;
  }
  Value_destroy(&usingval);
  if (pass==INTERPRET)
  {
    if (FS_flush(chn)==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
  }
  return (struct Value*)0;
}

struct Value *stmt_MATREAD(struct Value *value)
{
  ++pc.token;
  while (1)
  {
    struct Pc lvaluepc;
    struct Var *var;

    lvaluepc=pc;
    if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGMATIDENT);
    if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,GLOBALARRAY,0)==0)
    {
      return Value_new_ERROR(value,REDECLARATION);
    }
    var=&pc.token->u.identifier->sym->u.var;
    ++pc.token;
    if (pc.token->type==T_OP)
    {
      unsigned int dim,geometry[2];
      enum ValueType vartype=var->type;

      ++pc.token;
      if (evalGeometry(value,&dim,geometry)) return value;
      if (pass==INTERPRET)
      {
        Var_destroy(var);
        Var_new(var,vartype,dim,geometry,optionbase);
      }
    }
    if (pass==INTERPRET)
    {
      unsigned int i;
      int unused=1-var->base;

      if ((var->dim!=1 && var->dim!=2) || var->base<0 || var->base>1) return Value_new_ERROR(value,NOMATRIX,var->dim,var->base);
      if (var->dim==1)
      {
        for (i=unused; i<var->geometry[0]; ++i)
        {
          if (dataread(value,&(var->value[i])))
          {
            pc=lvaluepc;
            return value;
          }
        }
      }
      else
      {
        int j;

        for (i=unused; i<var->geometry[0]; ++i) for (j=unused; j<var->geometry[1]; ++j)
        {
          if (dataread(value,&(var->value[i*var->geometry[1]+j])))
          {
            pc=lvaluepc;
            return value;
          }
        }
      }
    }
    if (pc.token->type==T_COMMA) ++pc.token;
    else break;
  }
  return (struct Value*)0;
}

struct Value *stmt_MATREDIM(struct Value *value)
{
  ++pc.token;
  while (1)
  {
    struct Var *var;
    unsigned int dim,geometry[2];

    if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGMATIDENT);
    if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,GLOBALARRAY,0)==0)
    {
      return Value_new_ERROR(value,REDECLARATION);
    }
    var=&pc.token->u.identifier->sym->u.var;
    ++pc.token;
    if (pc.token->type!=T_OP) return Value_new_ERROR(value,MISSINGOP);
    ++pc.token;
    if (evalGeometry(value,&dim,geometry)) return value;
    if (pass==INTERPRET && Var_mat_redim(var,dim,geometry,value)!=(struct Value*)0) return value;
    if (pc.token->type==T_COMMA) ++pc.token;
    else break;
  }
  return (struct Value*)0;
}

struct Value *stmt_MATWRITE(struct Value *value)
{
  int chn=STDCHANNEL;
  int notfirst=0;
  int comma=0;

  ++pc.token;
  if (pc.token->type==T_CHANNEL)
  {
    ++pc.token;
    if (eval(value,_("channel"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
    chn=value->u.integer;
    Value_destroy(value);
    if (pc.token->type==T_COMMA) ++pc.token;
  }

  while (1)
  {
    struct Var *var;

    if (pc.token->type!=T_IDENTIFIER)
    {
      if (notfirst) break;
      return Value_new_ERROR(value,MISSINGMATIDENT);
    }
    notfirst=1;
    if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,GLOBALARRAY,0)==0)
    {
      return Value_new_ERROR(value,REDECLARATION);
    }
    var=&pc.token->u.identifier->sym->u.var;
    ++pc.token;
    if (pass==INTERPRET)
    {
      unsigned int i,j;
      int unused=1-var->base;
      int g0,g1;

      if ((var->dim!=1 && var->dim!=2) || var->base<0 || var->base>1) return Value_new_ERROR(value,NOMATRIX,var->dim,var->base);
      g0=var->geometry[0];
      g1=var->dim==1 ? unused+1 : var->geometry[1];
      for (i=unused; i<g0; ++i)
      {
        comma=0;
        for (j=unused; j<g1; ++j)
        {
          struct String s;

          String_new(&s);
          Value_clone(value,&(var->value[var->dim==1 ? i : i*g1+j]));
          if (comma) String_appendChar(&s,',');
          if (FS_putString(chn,Value_toWrite(value,&s))==-1)
          {
            Value_destroy(value);
            return Value_new_ERROR(value,IOERROR,FS_errmsg);
          }
          if (FS_flush(chn)==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
          String_destroy(&s);
          comma=1;
        }
        FS_putChar(chn,'\n');
      }
    }
    if (pc.token->type==T_COMMA || pc.token->type==T_SEMICOLON) ++pc.token;
    else break;
  }
  if (pass==INTERPRET)
  {
    if (FS_flush(chn)==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
  }
  return (struct Value*)0;
}

struct Value *stmt_NAME(struct Value *value)
{
  struct Pc namepc=pc;
  struct Value old;
  int res=-1,reserrno=-1;

  ++pc.token;
  if (eval(value,_("file name"))->type==V_ERROR || Value_retype(value,V_STRING)->type==V_ERROR) return value;
  if (pc.token->type!=T_AS)
  {
    Value_destroy(value);
    return Value_new_ERROR(value,MISSINGAS);
  }
  old=*value;
  ++pc.token;
  if (eval(value,_("file name"))->type==V_ERROR || Value_retype(value,V_STRING)->type==V_ERROR)
  {
    Value_destroy(&old);
    return value;
  }
  if (pass==INTERPRET)
  {
    res=rename(old.u.string.character,value->u.string.character);
    reserrno=errno;
  }
  Value_destroy(&old);
  Value_destroy(value);
  if (pass==INTERPRET && res==-1)
  {
    pc=namepc;
    return Value_new_ERROR(value,IOERROR,strerror(reserrno));
  }
  return (struct Value*)0;
}

struct Value *stmt_NEW(struct Value *value)
{
  if (pass==INTERPRET)
  {
    if (!DIRECTMODE) return Value_new_ERROR(value,NOTINPROGRAMMODE);
    new();
  }
  ++pc.token;
  return (struct Value*)0;
}

struct Value *stmt_NEXT(struct Value *value)
{
  struct Next **next=&pc.token->u.next;
  int level=0;

  if (pass==INTERPRET)
  {
    struct Value *l,inc;
    struct Pc savepc;

    ++pc.token;
    while (1)
    {
      /* get variable lvalue */
      savepc=pc;
      pc=(*next)[level].var;
      if ((l=lvalue(value))->type==V_ERROR) return value;
      pc=savepc;

      /* get limit value and increment */
      savepc=pc;
      pc=(*next)[level].limit;
      if (eval(value,_("limit"))->type==V_ERROR) return value;
      Value_retype(value,l->type);
      assert(value->type!=V_ERROR);
      if (pc.token->type==T_STEP)
      {
        ++pc.token;
        if (eval(&inc,_("step"))->type==V_ERROR)
        {
          Value_destroy(value);
          *value=inc;
          return value;
        }
      }
      else VALUE_NEW_INTEGER(&inc,1);
      VALUE_RETYPE(&inc,l->type);
      assert(inc.type!=V_ERROR);
      pc=savepc;

      Value_add(l,&inc,1);
      if (Value_exitFor(l,value,&inc))
      {
        Value_destroy(value);
        Value_destroy(&inc);
        if (pc.token->type==T_IDENTIFIER)
        {
          if (lvalue(value)->type==V_ERROR) return value;
          if (pc.token->type==T_COMMA) { ++pc.token; ++level; }
          else break;
        }
        else break;
      }
      else
      {
        pc=(*next)[level].body;
        Value_destroy(value);
        Value_destroy(&inc);
        break;
      }
    }
  }

  else
  {
    struct Pc *body;

    ++pc.token;
    while (1)
    {
      if ((body=popLabel(L_FOR_BODY))==(struct Pc*)0) return Value_new_ERROR(value,STRAYNEXT,topLabelDescription());
      if (level)
      {
        struct Next *more;

        more=realloc(*next,sizeof(struct Next)*(level+1));
        *next=more;
      }
      (*next)[level].body=*body;
      (*next)[level].limit=*popLabel(L_FOR_LIMIT);
      (*next)[level].var=*popLabel(L_FOR_VAR);
      (*next)[level].fr=*popLabel(L_FOR);
      if (pc.token->type==T_IDENTIFIER)
      {
        if (cistrcmp(pc.token->u.identifier->name,(*next)[level].var.token->u.identifier->name))
        {
          return Value_new_ERROR(value,FORMISMATCH);
        }
        if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,(pc.token+1)->type==T_OP?GLOBALARRAY:GLOBALVAR,0)==0)
        {
          return Value_new_ERROR(value,REDECLARATION);
        }
        if (lvalue(value)->type==V_ERROR) return value;
        if (pc.token->type==T_COMMA) { ++pc.token; ++level; }
        else break;
      }
      else break;
    }
    while (level>=0) (*next)[level--].fr.token->u.exitfor=pc;
  }

  return (struct Value*)0;
}

struct Value *stmt_ON(struct Value *value)
{
  struct On *on=&pc.token->u.on;

  ++pc.token;
  if (eval(value,_("selector"))->type==V_ERROR) return value;
  if (Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
  if (pass==INTERPRET)
  {
    struct Pc newpc;

    if (value->u.integer>0 && value->u.integer<on->pcLength)
    {
      newpc=on->pc[value->u.integer];
    }
    else newpc=on->pc[0];
    if (pc.token->type==T_GOTO) pc=newpc;
    else
    {
      pc=on->pc[0];
      Auto_pushGosubRet(&stack,&pc);
      pc=newpc;
    }
    Program_trace(&program,&pc,0,1);
  }
  else if (pass==DECLARE || pass==COMPILE)
  {
    Value_destroy(value);
    if (pc.token->type!=T_GOTO && pc.token->type!=T_GOSUB) return Value_new_ERROR(value,MISSINGGOTOSUB);
    ++pc.token;
    on->pcLength=1;
    while (1)
    {
      on->pc=realloc(on->pc,sizeof(struct Pc)*++on->pcLength);
      if (pc.token->type!=T_INTEGER) return Value_new_ERROR(value,MISSINGLINENUMBER);
      if (Program_goLine(&program,pc.token->u.integer,&on->pc[on->pcLength-1])==(struct Pc*)0) return Value_new_ERROR(value,NOSUCHLINE);
      if (pass==COMPILE && Program_scopeCheck(&program,&on->pc[on->pcLength-1],findLabel(L_FUNC))) return Value_new_ERROR(value,OUTOFSCOPE);
      ++pc.token;
      if (pc.token->type==T_COMMA) ++pc.token;
      else break;
    }
    on->pc[0]=pc;
  }
  return (struct Value*)0;
}

struct Value *stmt_ONERROR(struct Value *value)
{
  if (DIRECTMODE) return Value_new_ERROR(value,NOTINDIRECTMODE);
  ++pc.token;
  if (pass==INTERPRET)
  {
    stack.onerror=pc;
    Program_nextLine(&program,&pc);
    return (struct Value*)0;
  }
  else return &more_statements;
}

struct Value *stmt_ONERRORGOTO0(struct Value *value)
{
  if (DIRECTMODE) return Value_new_ERROR(value,NOTINDIRECTMODE);
  if (pass==INTERPRET)
  {
    stack.onerror.line=-1;
    if (stack.resumeable)
    {
      pc=stack.erpc;
      return Value_clone(value,&stack.err);
    }
  }
  ++pc.token;
  return (struct Value*)0;
}

struct Value *stmt_ONERROROFF(struct Value *value)
{
  if (DIRECTMODE) return Value_new_ERROR(value,NOTINDIRECTMODE);
  if (pass==INTERPRET) stack.onerror.line=-1;
  ++pc.token;
  return (struct Value*)0;
}

struct Value *stmt_OPEN(struct Value *value)
{
  int inout=-1,append=0;
  int mode=FS_ACCESS_NONE,lock=FS_LOCK_NONE;
  long int channel;
  long int recLength=-1;
  struct Pc errpc;
  struct Value recLengthValue;
  struct Pc statementpc=pc;

  ++pc.token;
  errpc=pc;
  if (eval(value,_("mode or file"))->type==V_ERROR || Value_retype(value,V_STRING)->type==V_ERROR) return value;
  if (pc.token->type==T_COMMA) /* parse MBASIC syntax */
  {
    if (value->u.string.length>=1)
    {
      switch (tolower(value->u.string.character[0]))
      {
        case 'i': inout=0; mode=FS_ACCESS_READ; break;
        case 'o': inout=1; mode=FS_ACCESS_WRITE; break;
        case 'a': inout=1; mode=FS_ACCESS_WRITE; append=1; break;
        case 'r': inout=3; mode=FS_ACCESS_READWRITE; break;
      }
    }
    Value_destroy(value);
    if (pass==INTERPRET && inout==-1)
    {
      pc=errpc;
      return Value_new_ERROR(value,BADMODE);
    }
    if (pc.token->type!=T_COMMA) return Value_new_ERROR(value,MISSINGCOMMA);
    ++pc.token;
    if (pc.token->type==T_CHANNEL) ++pc.token;
    errpc=pc;
    if (eval(value,_("channel"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR)
    {
      pc=errpc;
      return value;
    }
    channel=value->u.integer;
    Value_destroy(value);
    if (pass==INTERPRET && channel<0) return Value_new_ERROR(value,OUTOFRANGE,_("channel"));
    if (pc.token->type!=T_COMMA) return Value_new_ERROR(value,MISSINGCOMMA);
    ++pc.token;
    if (eval(value,_("file name"))->type==V_ERROR || Value_retype(value,V_STRING)->type==V_ERROR) return value;
    if (inout==3)
    {
      if (pc.token->type!=T_COMMA)
      {
        Value_destroy(value);
        return Value_new_ERROR(value,MISSINGCOMMA);
      }
      ++pc.token;
      errpc=pc;
      if (eval(&recLengthValue,_("record length"))->type==V_ERROR || Value_retype(&recLengthValue,V_INTEGER)->type==V_ERROR)
      {
        Value_destroy(value);
        *value=recLengthValue;
        return value;
      }
      recLength=recLengthValue.u.integer;
      Value_destroy(&recLengthValue);
      if (pass==INTERPRET && recLength<=0)
      {
        Value_destroy(value);
        pc=errpc;
        return Value_new_ERROR(value,OUTOFRANGE,_("record length"));
      }
    }
  }

  else /* parse ANSI syntax */
  {
    struct Value channelValue;
    int newMode;

    switch (pc.token->type)
    {
      case T_FOR_INPUT:  inout=0; mode=FS_ACCESS_READ; ++pc.token; break;
      case T_FOR_OUTPUT: inout=1; mode=FS_ACCESS_WRITE; ++pc.token; break;
      case T_FOR_APPEND: inout=1; mode=FS_ACCESS_WRITE; append=1; ++pc.token; break;
      case T_FOR_RANDOM: inout=3; mode=FS_ACCESS_READWRITE; ++pc.token; break;
      case T_FOR_BINARY: inout=4; mode=FS_ACCESS_READWRITE; ++pc.token; break;
      default: inout=3; mode=FS_ACCESS_READWRITE; break;
    }
    switch (pc.token->type)
    {
      case T_ACCESS_READ:       newMode=FS_ACCESS_READ;      break;
      case T_ACCESS_READ_WRITE: newMode=FS_ACCESS_READWRITE; break;
      case T_ACCESS_WRITE:      newMode=FS_ACCESS_WRITE;     break;
      default:                  newMode=FS_ACCESS_NONE;
    }
    if (newMode!=FS_ACCESS_NONE)
    {
      if ((newMode&mode)==0) return Value_new_ERROR(value,WRONGMODE);
      mode=newMode;
      ++pc.token;
    }
    switch (pc.token->type)
    {
      case T_SHARED:          lock=FS_LOCK_NONE;      ++pc.token; break;
      case T_LOCK_READ:       lock=FS_LOCK_SHARED;    ++pc.token; break;
      case T_LOCK_WRITE:      lock=FS_LOCK_EXCLUSIVE; ++pc.token; break;
      default: ;
    }
    if (pc.token->type!=T_AS)
    {
      Value_destroy(value);
      return Value_new_ERROR(value,MISSINGAS);
    }
    ++pc.token;
    if (pc.token->type==T_CHANNEL) ++pc.token;
    errpc=pc;
    if (eval(&channelValue,_("channel"))->type==V_ERROR || Value_retype(&channelValue,V_INTEGER)->type==V_ERROR)
    {
      pc=errpc;
      Value_destroy(value);
      *value=channelValue;
      return value;
    }
    channel=channelValue.u.integer;
    Value_destroy(&channelValue);
    if (inout==3)
    {
      if (pc.token->type==T_IDENTIFIER)
      {
        if (cistrcmp(pc.token->u.identifier->name,"len"))
        {
          Value_destroy(value);
          return Value_new_ERROR(value,MISSINGLEN);
        }
        ++pc.token;
        if (pc.token->type!=T_EQ)
        {
          Value_destroy(value);
          return Value_new_ERROR(value,MISSINGEQ);
        }
        ++pc.token;
        errpc=pc;
        if (eval(&recLengthValue,_("record length"))->type==V_ERROR || Value_retype(&recLengthValue,V_INTEGER)->type==V_ERROR)
        {
          Value_destroy(value);
          *value=recLengthValue;
          return value;
        }
        recLength=recLengthValue.u.integer;
        Value_destroy(&recLengthValue);
        if (pass==INTERPRET && recLength<=0)
        {
          Value_destroy(value);
          pc=errpc;
          return Value_new_ERROR(value,OUTOFRANGE,_("record length"));
        }
      }
      else recLength=1;
    }
  }

  /* open file with name value */
  if (pass==INTERPRET)
  {
    int res=-1;

    if (inout==0) res=FS_openinChn(channel,value->u.string.character,mode);
    else if (inout==1) res=FS_openoutChn(channel,value->u.string.character,mode,append);
    else if (inout==3) res=FS_openrandomChn(channel,value->u.string.character,mode,recLength);
    else if (inout==4) res=FS_openbinaryChn(channel,value->u.string.character,mode);
    if (res==-1)
    {
      pc=statementpc;
      Value_destroy(value);
      return Value_new_ERROR(value,IOERROR,FS_errmsg);
    }
    else
    {
      if (lock!=FS_LOCK_NONE && FS_lock(channel,0,0,lock,0)==-1)
      {
        pc=statementpc;
        Value_destroy(value);
        Value_new_ERROR(value,IOERROR,FS_errmsg);
        FS_close(channel);
        return value;
      }
    }
  }

  Value_destroy(value);
  return (struct Value*)0;
}

struct Value *stmt_OPTIONBASE(struct Value *value)
{
  ++pc.token;
  if (eval(value,_("array subscript base"))->type==V_ERROR || (pass!=DECLARE && Value_retype(value,V_INTEGER)->type==V_ERROR)) return value;
  if (pass==INTERPRET) optionbase=value->u.integer;
  Value_destroy(value);
  return (struct Value*)0;
}

struct Value *stmt_OPTIONRUN(struct Value *value)
{
  ++pc.token;
  if (pass==INTERPRET)
    {
      FS_xonxoff(STDCHANNEL,0);
    }

  return (struct Value*)0;
}

struct Value *stmt_OPTIONSTOP(struct Value *value)
{
  ++pc.token;
  if (pass==INTERPRET)
    {
      FS_xonxoff(STDCHANNEL,1);
    }

  return (struct Value*)0;
}

struct Value *stmt_OUT_POKE(struct Value *value)
{
  int out,address,val;
  struct Pc lpc;

  out=(pc.token->type==T_OUT);
  lpc=pc;
  ++pc.token;
  if (eval(value,_("address"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
  address=value->u.integer;
  Value_destroy(value);
  if (pc.token->type!=T_COMMA) return Value_new_ERROR(value,MISSINGCOMMA);
  ++pc.token;
  if (eval(value,_("output value"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
  val=value->u.integer;
  Value_destroy(value);
  if (pass==INTERPRET)
  {
    if ((out ? FS_portOutput : FS_memOutput)(address,val)==-1)
    {
      pc=lpc;
      return Value_new_ERROR(value,IOERROR,FS_errmsg);
    }
  }
  return (struct Value*)0;
}

struct Value *stmt_PRINT_LPRINT(struct Value *value)
{
  int nl=1;
  int chn=(pc.token->type==T_PRINT?STDCHANNEL:LPCHANNEL);
  int printusing=0;
  struct Value usingval;
  struct String *using=(struct String*)0;
  size_t usingpos=0;

  ++pc.token;
  if (chn==STDCHANNEL && pc.token->type==T_CHANNEL)
  {
    ++pc.token;
    if (eval(value,_("channel"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
    chn=value->u.integer;
    Value_destroy(value);
    if (pc.token->type==T_COMMA) ++pc.token;
  }

  if (pc.token->type==T_USING)
  {
    struct Pc usingpc;

    usingpc=pc;
    printusing=1;
    ++pc.token;
    if (pc.token->type==T_INTEGER)
    {
      if (pass==COMPILE && Program_imageLine(&program,pc.token->u.integer,&usingpc.token->u.image)==(struct Pc*)0) return Value_new_ERROR(value,NOSUCHIMAGELINE);
      else if (pass==INTERPRET) using=usingpc.token->u.image.token->u.string;
      Value_new_STRING(&usingval);
      ++pc.token;
    }
    else
    {
      if (eval(&usingval,_("format string"))->type==V_ERROR || Value_retype(&usingval,V_STRING)->type==V_ERROR)
      {
        *value=usingval;
        return value;
      }
      using=&usingval.u.string;
    }
    if (pc.token->type!=T_SEMICOLON)
    {
      Value_destroy(&usingval);
      return Value_new_ERROR(value,MISSINGSEMICOLON);
    }
    ++pc.token;
  }

  else
  {
    Value_new_STRING(&usingval);
    using=&usingval.u.string;
  }
  while (1)
  {
    struct Pc valuepc;

    valuepc=pc;
    if (eval(value,(const char*)0))
    {
      if (value->type==V_ERROR)
      {
        Value_destroy(&usingval);
        return value;
      }
      if (pass==INTERPRET)
      {
        struct String s;

        String_new(&s);
        if (Value_toStringUsing(value,&s,using,&usingpos)->type==V_ERROR)
        {
          Value_destroy(&usingval);
          String_destroy(&s);
          pc=valuepc;
          return value;
        }
        if (FS_putItem(chn,&s)==-1)
        {
          Value_destroy(&usingval);
          Value_destroy(value);
          String_destroy(&s);
          return Value_new_ERROR(value,IOERROR,FS_errmsg);
        }
        String_destroy(&s);
      }
      Value_destroy(value);
      nl=1;
    }

    else if (pc.token->type==T_TAB || pc.token->type==T_SPC)
    {
      int tab=pc.token->type==T_TAB;

      ++pc.token;
      if (pc.token->type!=T_OP)
      {
        Value_destroy(&usingval);
        return Value_new_ERROR(value,MISSINGOP);
      }
      ++pc.token;
      if (eval(value,_("count"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR)
      {
        Value_destroy(&usingval);
        return value;
      }
      if (pass==INTERPRET)
      {
        int s=value->u.integer;
        int r=0;

        if (tab) r=FS_tab(chn,s);
        else while (s-->0 && (r=FS_putChar(chn,' '))!=-1);
        if (r==-1)
        {
          Value_destroy(&usingval);
          Value_destroy(value);
          return Value_new_ERROR(value,IOERROR,FS_errmsg);
        }
      }
      Value_destroy(value);
      if (pc.token->type!=T_CP)
      {
        Value_destroy(&usingval);
        return Value_new_ERROR(value,MISSINGCP);
      }
      ++pc.token;
      nl=1;
    }

    else if (pc.token->type==T_SEMICOLON)
    {
      ++pc.token;
      nl=0;
    }

    else if (pc.token->type==T_COMMA)
    {
      ++pc.token;
      if (pass==INTERPRET && !printusing) FS_nextcol(chn);
      nl=0;
    }

    else break;
    if (pass==INTERPRET && FS_flush(chn)==-1)
    {
      Value_destroy(&usingval);
      return Value_new_ERROR(value,IOERROR,FS_errmsg);
    }
  }
  Value_destroy(&usingval);
  if (pass==INTERPRET)
  {
    if (nl && FS_putChar(chn,'\n')==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
    if (FS_flush(chn)==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
  }
  return (struct Value*)0;
}

struct Value *stmt_RANDOMIZE(struct Value *value)
{
  struct Pc argpc;

  ++pc.token;
  argpc=pc;
  if (eval(value,(const char*)0))
  {
    Value_retype(value,V_INTEGER);
    if (value->type==V_ERROR)
    {
      pc=argpc;
      Value_destroy(value);
      return Value_new_ERROR(value,MISSINGEXPR,_("random number generator seed"));
    }
    if (pass==INTERPRET) srand(pc.token->u.integer);
    Value_destroy(value);
  }
  else srand(getpid()^time((time_t*)0));
  return (struct Value*)0;
}

struct Value *stmt_READ(struct Value *value)
{
  ++pc.token;
  while (1)
  {
    struct Value *l;
    struct Pc lvaluepc;

    lvaluepc=pc;
    if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGREADIDENT);
    if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,(pc.token+1)->type==T_OP?GLOBALARRAY:GLOBALVAR,0)==0)
    {
      return Value_new_ERROR(value,REDECLARATION);
    }
    if ((l=lvalue(value))->type==V_ERROR) return value;
    if (pass==INTERPRET && dataread(value,l))
    {
      pc=lvaluepc;
      return value;
    }
    if (pc.token->type==T_COMMA) ++pc.token;
    else break;
  }
  return (struct Value*)0;
}

struct Value *stmt_COPY_RENAME(struct Value *value)
{
  struct Pc argpc;
  struct Value from;
  struct Pc statementpc=pc;

  ++pc.token;
  argpc=pc;
  if (eval(&from,_("source file"))->type==V_ERROR || (pass!=DECLARE && Value_retype(&from,V_STRING)->type==V_ERROR))
  {
    pc=argpc;
    *value=from;
    return value;
  }
  if (pc.token->type!=T_TO)
  {
    Value_destroy(&from);
    return Value_new_ERROR(value,MISSINGTO);
  }
  ++pc.token;
  argpc=pc;
  if (eval(value,_("destination file"))->type==V_ERROR || (pass!=DECLARE && Value_retype(value,V_STRING)->type==V_ERROR))
  {
    pc=argpc;
    return value;
  }
  if (pass==INTERPRET)
  {
    const char *msg;
    int res;

    if (statementpc.token->type==T_RENAME)
    {
      res=rename(from.u.string.character,value->u.string.character);
      msg=strerror(errno);
    }
    else
    {
      res=FS_copy(from.u.string.character,value->u.string.character);
      msg=FS_errmsg;
    }
    if (res==-1)
    {
      Value_destroy(&from);
      Value_destroy(value);
      pc=statementpc;
      return Value_new_ERROR(value,IOERROR,msg);
    }
  }
  Value_destroy(&from);
  Value_destroy(value);
  return (struct Value*)0;
}

struct Value *stmt_RENUM(struct Value *value)
{
  int first=10,inc=10;

  ++pc.token;
  if (pc.token->type==T_INTEGER)
  {
    first=pc.token->u.integer;
    ++pc.token;
    if (pc.token->type==T_COMMA)
    {
      ++pc.token;
      if (pc.token->type!=T_INTEGER) return Value_new_ERROR(value,MISSINGINCREMENT);
      inc=pc.token->u.integer;
      ++pc.token;
    }
  }
  if (pass==INTERPRET)
  {
    if (!DIRECTMODE) return Value_new_ERROR(value,NOTINPROGRAMMODE);
    Program_renum(&program,first,inc);
  }
  return (struct Value*)0;
}

struct Value *stmt_REPEAT(struct Value *value)
{
  if (pass==DECLARE || pass==COMPILE) pushLabel(L_REPEAT,&pc);
  ++pc.token;
  return (struct Value*)0;
}

struct Value *stmt_RESTORE(struct Value *value)
{
  struct Token *restorepc=pc.token;

  if (pass==INTERPRET) curdata=pc.token->u.restore;
  ++pc.token;
  if (pc.token->type==T_INTEGER)
  {
    if (pass==COMPILE && Program_dataLine(&program,pc.token->u.integer,&restorepc->u.restore)==(struct Pc*)0) return Value_new_ERROR(value,NOSUCHDATALINE);
    ++pc.token;
  }
  else if (pass==COMPILE) restorepc->u.restore=stack.begindata;
  return (struct Value*)0;
}

struct Value *stmt_RETURN(struct Value *value)
{
  if (pass==DECLARE || pass==COMPILE) ++pc.token;
  if (pass==INTERPRET)
  {
    if (Auto_gosubReturn(&stack,&pc)) Program_trace(&program,&pc,0,1);
    else return Value_new_ERROR(value,STRAYRETURN);
  }
  return (struct Value*)0;
}

struct Value *stmt_RUN(struct Value *value)
{
  struct Pc argpc,begin;

  stack.resumeable=0;
  ++pc.token;
  argpc=pc;
  if (pc.token->type==T_INTEGER)
  {
    if (Program_goLine(&program,pc.token->u.integer,&begin)==(struct Pc*)0) return Value_new_ERROR(value,NOSUCHLINE);
    if (pass==COMPILE && Program_scopeCheck(&program,&begin,findLabel(L_FUNC))) return Value_new_ERROR(value,OUTOFSCOPE);
    ++pc.token;
  }
  else if (eval(value,(const char*)0))
  {
    if (value->type==V_ERROR || Value_retype(value,V_STRING)->type==V_ERROR)
    {
      pc=argpc;
      return value;
    }
    else if (pass==INTERPRET)
    {
      int chn;
      struct Program newprogram;

      if ((chn=FS_openin(value->u.string.character))==-1)
      {
        pc=argpc;
        Value_destroy(value);
        return Value_new_ERROR(value,IOERROR,FS_errmsg);
      }
      Value_destroy(value);
      Program_new(&newprogram);
      if (Program_merge(&newprogram,chn,value))
      {
        pc=argpc;
        Program_destroy(&newprogram);
        return value;
      }
      FS_close(chn);
      new();
      Program_destroy(&program);
      program=newprogram;
      if (Program_beginning(&program,&begin)==(struct Pc*)0)
      {
        return Value_new_ERROR(value,NOPROGRAM);
      }
    }
    else Value_destroy(value);
  }
  else
  {
    if (Program_beginning(&program,&begin)==(struct Pc*)0)
    {
      return Value_new_ERROR(value,NOPROGRAM);
    }
  }
  if (pass==INTERPRET)
  {
    if (compileProgram(value,1)->type==V_ERROR) return value;
    pc=begin;
    curdata=stack.begindata;
    Global_clear(&globals);
    FS_closefiles();
    Program_trace(&program,&pc,0,1);
  }
  return (struct Value*)0;
}

struct Value *stmt_SAVE(struct Value *value)
{
  struct Pc loadpc;
  int name;

  if (pass==INTERPRET && !DIRECTMODE) return Value_new_ERROR(value,NOTINPROGRAMMODE);
  ++pc.token;
  loadpc=pc;
  if (pc.token->type==T_EOL && program.name.length)
  {
    name=0;
  }
  else
  {
    name=1;
    if (eval(value,_("file name"))->type==V_ERROR || Value_retype(value,V_STRING)->type==V_ERROR)
    {
      pc=loadpc;
      return value;
    }
  }
  if (pass==INTERPRET)
  {
    int chn;

    if (name) Program_setname(&program,value->u.string.character);
    if ((chn=FS_openout(program.name.character))==-1)
    {
      pc=loadpc;
      if (name) Value_destroy(value);
      return Value_new_ERROR(value,IOERROR,FS_errmsg);
    }
    FS_width(chn,0);
    if (name) Value_destroy(value);
    if (Program_list(&program,chn,0,(struct Pc*)0,(struct Pc*)0,value))
    {
      pc=loadpc;
      return value;
    }
    FS_close(chn);
    program.unsaved=0;
  }
  else if (name) Value_destroy(value);
  return (struct Value*)0;
}

struct Value *stmt_SELECTCASE(struct Value *value)
{
  struct Pc statementpc=pc;

  if (pass==DECLARE || pass==COMPILE) pushLabel(L_SELECTCASE,&pc);
  ++pc.token;
  if (eval(value,_("selector"))->type==V_ERROR) return value;
  if (pass==DECLARE || pass==COMPILE)
  {
    statementpc.token->u.selectcase->type=value->type;
    statementpc.token->u.selectcase->nextcasevalue.line=-1;
  }
  else
  {
    struct Pc casevaluepc;
    int match=0;

    pc=casevaluepc=statementpc.token->u.selectcase->nextcasevalue;
    do
    {
      ++pc.token;
      switch (casevaluepc.token->type)
      {
        case T_CASEVALUE:
        {
          do
          {
            struct Value casevalue1;

            if (pc.token->type==T_IS)
            {
              enum TokenType relop;

              ++pc.token;
              relop=pc.token->type;
              ++pc.token;
              if (eval(&casevalue1,"`is'")->type==V_ERROR)
              {
                Value_destroy(value);
                *value=casevalue1;
                return value;
              }
              Value_retype(&casevalue1,statementpc.token->u.selectcase->type);
              assert(casevalue1.type!=V_ERROR);
              if (!match)
              {
                struct Value cmp;

                Value_clone(&cmp,value);
                switch (relop)
                {
                  case T_LT: Value_lt(&cmp,&casevalue1,1); break;
                  case T_LE: Value_le(&cmp,&casevalue1,1); break;
                  case T_EQ: Value_eq(&cmp,&casevalue1,1); break;
                  case T_GE: Value_ge(&cmp,&casevalue1,1); break;
                  case T_GT: Value_gt(&cmp,&casevalue1,1); break;
                  case T_NE: Value_ne(&cmp,&casevalue1,1); break;
                  default: assert(0);
                }
                assert(cmp.type==V_INTEGER);
                match=cmp.u.integer;
                Value_destroy(&cmp);
              }

              Value_destroy(&casevalue1);
            }
            else
            {
              if (eval(&casevalue1,"`case'")->type==V_ERROR)
              {
                Value_destroy(value);
                *value=casevalue1;
                return value;
              }
              Value_retype(&casevalue1,statementpc.token->u.selectcase->type);
              assert(casevalue1.type!=V_ERROR);
              if (pc.token->type==T_TO) /* match range */
              {
                struct Value casevalue2;

                ++pc.token;
                if (eval(&casevalue2,"`case'")->type==V_ERROR)
                {
                  Value_destroy(&casevalue1);
                  Value_destroy(value);
                  *value=casevalue2;
                  return value;
                }
                Value_retype(&casevalue2,statementpc.token->u.selectcase->type);
                assert(casevalue2.type!=V_ERROR);
                if (!match)
                {
                  struct Value cmp1,cmp2;

                  Value_clone(&cmp1,value);
                  Value_clone(&cmp2,value);
                  Value_ge(&cmp1,&casevalue1,1);
                  assert(cmp1.type==V_INTEGER);
                  Value_le(&cmp2,&casevalue2,1);
                  assert(cmp2.type==V_INTEGER);
                  match=cmp1.u.integer && cmp2.u.integer;
                  Value_destroy(&cmp1);
                  Value_destroy(&cmp2);
                }
                Value_destroy(&casevalue2);
              }

              else /* match value */
              {
                if (!match)
                {
                  struct Value cmp;

                  Value_clone(&cmp,value);
                  Value_eq(&cmp,&casevalue1,1);
                  assert(cmp.type==V_INTEGER);
                  match=cmp.u.integer;
                  Value_destroy(&cmp);
                }
              }

              Value_destroy(&casevalue1);
            }
            if (pc.token->type==T_COMMA) ++pc.token;
            else break;
          } while (1);
          break;
        }

        case T_CASEELSE:
        {
          match=1;
          break;
        }

        default: assert(0);
      }
      if (!match)
      {
        if (casevaluepc.token->u.casevalue->nextcasevalue.line!=-1)
        {
          pc=casevaluepc=casevaluepc.token->u.casevalue->nextcasevalue;
        }
        else
        {
          pc=statementpc.token->u.selectcase->endselect;
          break;
        }
      }
    } while (!match);
  }
  Value_destroy(value);
  return (struct Value*)0;
}

struct Value *stmt_SHELL(struct Value *value)
{
#ifdef CONFIG_ARCH_HAVE_VFORK
  pid_t pid;
  int status;

  ++pc.token;
  if (eval(value,(const char*)0))
  {
    if (value->type==V_ERROR || Value_retype(value,V_STRING)->type==V_ERROR) return value;
    if (pass==INTERPRET)
    {
      if (run_restricted)
      {
        Value_destroy(value);
        return Value_new_ERROR(value,RESTRICTED,strerror(errno));
      }
      FS_shellmode(STDCHANNEL);
      switch (pid=vfork())
      {
        case -1:
        {
          FS_fsmode(STDCHANNEL);
          Value_destroy(value);
          return Value_new_ERROR(value,FORKFAILED,strerror(errno));
        }
        case 0:
        {
          execl("/bin/sh","sh","-c",value->u.string.character,(const char*)0);
          exit(127);
        }
        default:
        {
          while (waitpid(pid,&status,0)==-1 && errno!=EINTR);
        }
      }
      FS_fsmode(STDCHANNEL);
    }
    Value_destroy(value);
  }
  else
  {
    if (pass==INTERPRET)
    {
      if (run_restricted)
      {
        return Value_new_ERROR(value,RESTRICTED,strerror(errno));
      }
      FS_shellmode(STDCHANNEL);
      switch (pid=vfork())
      {
        case -1:
        {
          FS_fsmode(STDCHANNEL);
          return Value_new_ERROR(value,FORKFAILED,strerror(errno));
        }
        case 0:
        {
          const char *shell;

          shell=getenv("SHELL");
          if (shell==(const char*)0) shell="/bin/sh";
          execl(shell,(strrchr(shell,'/') ? strrchr(shell,'/')+1 : shell),(const char*)0);
          exit(127);
        }
        default:
        {
          while (waitpid(pid,&status,0)==-1 && errno!=EINTR);
        }
      }
      FS_fsmode(STDCHANNEL);
    }
  }
  return (struct Value*)0;
#else
  return Value_new_ERROR(value,FORKFAILED,strerror(ENOSYS));
#endif
}

struct Value *stmt_SLEEP(struct Value *value)
{
  ++pc.token;
  if (eval(value,_("pause"))->type==V_ERROR || Value_retype(value,V_REAL)->type==V_ERROR) return value;
  {
    double s=value->u.real;

    Value_destroy(value);
    if (pass==INTERPRET)
    {
      if (s<0.0) return Value_new_ERROR(value,OUTOFRANGE,_("pause"));
      FS_sleep(s);
    }
  }
  return (struct Value*)0;
}

struct Value *stmt_STOP(struct Value *value)
{
  if (pass!=INTERPRET)
    {
      ++pc.token;
    }

  return (struct Value*)0;
}

struct Value *stmt_SUBEXIT(struct Value *value)
{
  struct Pc *curfn=(struct Pc*)0;

  if (pass==DECLARE || pass==COMPILE)
  {
    if ((curfn=findLabel(L_FUNC))==(struct Pc*)0 || (curfn->token+1)->u.identifier->defaultType!=V_VOID)
    {
      return Value_new_ERROR(value,STRAYSUBEXIT);
    }
  }
  ++pc.token;
  if (pass==INTERPRET) return Value_new_VOID(value);
  return (struct Value*)0;
}

struct Value *stmt_SWAP(struct Value *value)
{
  struct Value *l1,*l2;
  struct Pc lvaluepc;

  ++pc.token;
  lvaluepc=pc;
  if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGSWAPIDENT);
  if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,(pc.token+1)->type==T_OP?GLOBALARRAY:GLOBALVAR,0)==0)
  {
    return Value_new_ERROR(value,REDECLARATION);
  }
  if ((l1=lvalue(value))->type==V_ERROR) return value;
  if (pc.token->type==T_COMMA) ++pc.token;
  else return Value_new_ERROR(value,MISSINGCOMMA);
  lvaluepc=pc;
  if (pc.token->type!=T_IDENTIFIER) return Value_new_ERROR(value,MISSINGSWAPIDENT);
  if (pass==DECLARE && Global_variable(&globals,pc.token->u.identifier,pc.token->u.identifier->defaultType,(pc.token+1)->type==T_OP?GLOBALARRAY:GLOBALVAR,0)==0)
  {
    return Value_new_ERROR(value,REDECLARATION);
  }
  if ((l2=lvalue(value))->type==V_ERROR) return value;
  if (l1->type!=l2->type)
  {
    pc=lvaluepc;
    return Value_new_typeError(value,l2->type,l1->type);
  }
  if (pass==INTERPRET)
  {
    struct Value foo;

    foo=*l1;
    *l1=*l2;
    *l2=foo;
  }
  return (struct Value*)0;
}

struct Value *stmt_SYSTEM(struct Value *value)
{
  ++pc.token;
  if (pass==INTERPRET)
  {
    if (program.unsaved)
    {
      int ch;

      FS_putChars(STDCHANNEL,_("Quit without saving? (y/n) "));
      FS_flush(STDCHANNEL);
      if ((ch=FS_getChar(STDCHANNEL))!=-1)
      {
        FS_putChar(STDCHANNEL,ch);
        FS_flush(STDCHANNEL);
        FS_nextline(STDCHANNEL);
        if (tolower(ch)==*_("yes"))
        {
          bas_exit();
          exit(0);
        }
      }
    }
    else
    {
      bas_exit();
      exit(0);
    }
  }
  return (struct Value*)0;
}

struct Value *stmt_TROFF(struct Value *value)
{
  ++pc.token;
  program.trace=0;
  return (struct Value*)0;
}

struct Value *stmt_TRON(struct Value *value)
{
  ++pc.token;
  program.trace=1;
  return (struct Value*)0;
}

struct Value *stmt_TRUNCATE(struct Value *value)
{
  struct Pc chnpc;
  int chn;

  chnpc=pc;
  ++pc.token;
  if (pc.token->type==T_CHANNEL) ++pc.token;
  if (eval(value,(const char*)0)==(struct Value*)0)
  {
    return Value_new_ERROR(value,MISSINGEXPR,_("channel"));
  }
  if (value->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
  chn=value->u.integer;
  Value_destroy(value);
  if (pass==INTERPRET && FS_truncate(chn)==-1)
  {
    pc=chnpc;
    return Value_new_ERROR(value,IOERROR,FS_errmsg);
  }
  return (struct Value*)0;
}

struct Value *stmt_UNNUM(struct Value *value)
{
  ++pc.token;
  if (pass==INTERPRET)
  {
    if (!DIRECTMODE) return Value_new_ERROR(value,NOTINPROGRAMMODE);
    Program_unnum(&program);
  }
  return (struct Value*)0;
}

struct Value *stmt_UNTIL(struct Value *value)
{
  struct Pc untilpc=pc;
  struct Pc *repeatpc;

  ++pc.token;
  if (eval(value,_("condition"))->type==V_ERROR) return value;
  if (pass==INTERPRET)
  {
    if (Value_isNull(value)) pc=untilpc.token->u.until;
    Value_destroy(value);
  }
  if (pass==DECLARE || pass==COMPILE)
  {
    if ((repeatpc=popLabel(L_REPEAT))==(struct Pc*)0) return Value_new_ERROR(value,STRAYUNTIL);
    untilpc.token->u.until=*repeatpc;
  }
  return (struct Value*)0;
}

struct Value *stmt_WAIT(struct Value *value)
{
  int address,mask,sel=-1,usesel;
  struct Pc lpc;

  lpc=pc;
  ++pc.token;
  if (eval(value,_("address"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
  address=value->u.integer;
  Value_destroy(value);
  if (pc.token->type!=T_COMMA) return Value_new_ERROR(value,MISSINGCOMMA);
  ++pc.token;
  if (eval(value,_("mask"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
  mask=value->u.integer;
  Value_destroy(value);
  if (pc.token->type==T_COMMA)
  {
    ++pc.token;
    if (eval(value,_("select"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
    sel=value->u.integer;
    usesel=1;
    Value_destroy(value);
  }
  else usesel=0;
  if (pass==INTERPRET)
  {
    int v;

    do
    {
      if ((v=FS_portInput(address))==-1)
      {
        pc=lpc;
        return Value_new_ERROR(value,IOERROR,FS_errmsg);
      }
    } while ((usesel ? (v^sel)&mask : v^mask)==0);
  }
  return (struct Value*)0;
}

struct Value *stmt_WHILE(struct Value *value)
{
  struct Pc whilepc=pc;

  if (pass==DECLARE || pass==COMPILE) pushLabel(L_WHILE,&pc);
  ++pc.token;
  if (eval(value,_("condition"))->type==V_ERROR) return value;
  if (pass==INTERPRET)
  {
    if (Value_isNull(value)) pc=*whilepc.token->u.afterwend;
    Value_destroy(value);
  }
  return (struct Value*)0;
}

struct Value *stmt_WEND(struct Value *value)
{
  if (pass==DECLARE || pass==COMPILE)
  {
    struct Pc *whilepc;

    if ((whilepc=popLabel(L_WHILE))==(struct Pc*)0) return Value_new_ERROR(value,STRAYWEND,topLabelDescription());
    *pc.token->u.whilepc=*whilepc;
    ++pc.token;
    *(whilepc->token->u.afterwend)=pc;
  }
  else pc=*pc.token->u.whilepc;
  return (struct Value*)0;
}

struct Value *stmt_WIDTH(struct Value *value)
{
  int chn=STDCHANNEL,width;

  ++pc.token;
  if (pc.token->type==T_CHANNEL)
  {
    ++pc.token;
    if (eval(value,_("channel"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
    chn=value->u.integer;
    Value_destroy(value);
    if (pc.token->type==T_COMMA) ++pc.token;
  }

  if (eval(value,(const char*)0))
  {
    if (value->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
    width=value->u.integer;
    Value_destroy(value);
    if (pass==INTERPRET && FS_width(chn,width)==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
  }
  if (pc.token->type==T_COMMA)
  {
    ++pc.token;
    if (eval(value,_("zone width"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
    width=value->u.integer;
    Value_destroy(value);
    if (pass==INTERPRET && FS_zone(chn,width)==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
  }

  return (struct Value*)0;
}

struct Value *stmt_WRITE(struct Value *value)
{
  int chn=STDCHANNEL;
  int comma=0;

  ++pc.token;
  if (pc.token->type==T_CHANNEL)
  {
    ++pc.token;
    if (eval(value,_("channel"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
    chn=value->u.integer;
    Value_destroy(value);
    if (pc.token->type==T_COMMA) ++pc.token;
  }

  while (1)
  {
    if (eval(value,(const char*)0))
    {
      if (value->type==V_ERROR) return value;
      if (pass==INTERPRET)
      {
        struct String s;

        String_new(&s);
        if (comma) String_appendChar(&s,',');
        if (FS_putString(chn,Value_toWrite(value,&s))==-1)
        {
          Value_destroy(value);
          return Value_new_ERROR(value,IOERROR,FS_errmsg);
        }
        if (FS_flush(chn)==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
        String_destroy(&s);
      }
      Value_destroy(value);
      comma=1;
    }
    else if (pc.token->type==T_COMMA || pc.token->type==T_SEMICOLON) ++pc.token;
    else break;
  }
  if (pass==INTERPRET)
  {
    FS_putChar(chn,'\n');
    if (FS_flush(chn)==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
  }
  return (struct Value*)0;
}

struct Value *stmt_XREF(struct Value *value)
{
  stack.resumeable=0;
  ++pc.token;
  if (pass==INTERPRET)
  {
    if (!program.runnable && compileProgram(value,1)->type==V_ERROR) return value;
    Program_xref(&program,STDCHANNEL);
  }
  return (struct Value*)0;
}

struct Value *stmt_ZONE(struct Value *value)
{
  int chn=STDCHANNEL,width;

  ++pc.token;
  if (pc.token->type==T_CHANNEL)
  {
    ++pc.token;
    if (eval(value,_("channel"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
    chn=value->u.integer;
    Value_destroy(value);
    if (pc.token->type==T_COMMA) ++pc.token;
  }

  if (eval(value,_("zone width"))->type==V_ERROR || Value_retype(value,V_INTEGER)->type==V_ERROR) return value;
  width=value->u.integer;
  Value_destroy(value);
  if (pass==INTERPRET && FS_zone(chn,width)==-1) return Value_new_ERROR(value,IOERROR,FS_errmsg);
  return (struct Value*)0;
}