Use SIGCHLD with waitpid(); implemented wait() and waitid()

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5515 42af7a65-404d-4744-a932-0658087f49c3

3 files changed, 11 insertions, 8 deletions

diff --git a/nuttx/include/nuttx/sched.h b/nuttx/include/nuttx/sched.h
index 6c67e1500..b2ec1cee4 100644
--- a/nuttx/include/nuttx/sched.h
+++ b/nuttx/include/nuttx/sched.h
@@ -1,7 +1,7 @@
 /********************************************************************************
  * include/nuttx/sched.h
  *
- *   Copyright (C) 2007-2012 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2013 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -204,6 +204,7 @@ struct _TCB
   pid_t    pid;                          /* This is the ID of the thread        */
 #ifdef CONFIG_SCHED_HAVE_PARENT
   pid_t    parent;                       /* This is the ID of the parent thread */
+  uint16_t nchildren;                    /* This is the number active children  */
 #endif
   start_t  start;                        /* Thread start function               */
   entry_t  entry;                        /* Entry Point into the thread         */
@@ -226,7 +227,7 @@ struct _TCB
 # endif
 #endif
 
-#ifdef CONFIG_SCHED_WAITPID
+#if defined(CONFIG_SCHED_WAITPID) && !defined(CONFIG_SCHED_HAVE_PARENT)
   sem_t    exitsem;                      /* Support for waitpid                 */
   int     *stat_loc;                     /* Location to return exit status      */
 #endif
diff --git a/nuttx/include/sys/types.h b/nuttx/include/sys/types.h
index 2ae69d4a7..95feee72e 100644
--- a/nuttx/include/sys/types.h
+++ b/nuttx/include/sys/types.h
@@ -154,7 +154,9 @@ typedef uint16_t     dev_t;
 
 typedef uint16_t     ino_t;
 
-/* pid_t is used for process IDs and process group IDs */
+/* pid_t is used for process IDs and process group IDs. It must be signed because
+ * negative PID values are used to represent invalid PIDs.
+ */
 
 typedef int          pid_t;
 
diff --git a/nuttx/include/sys/wait.h b/nuttx/include/sys/wait.h
index 6af1e971e..2476adef9 100644
--- a/nuttx/include/sys/wait.h
+++ b/nuttx/include/sys/wait.h
@@ -1,7 +1,7 @@
 /****************************************************************************
  * include/sys/wait.h
  *
- *   Copyright (C) 2011 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2011, 2013 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -66,7 +66,7 @@
 #define WTERMSIG(s)     (false)  /* Return signal number that caused process to terminate */
 
 /* The following symbolic constants are possible values for the options
- * argument to waitpi(1) (1) and/or waitid() (2),
+ * argument to waitpid() (1) and/or waitid() (2),
  */
 
 #define WCONTINUED      (1 << 0) /* Status for child that has been continued (1)(2) */
@@ -104,9 +104,9 @@ extern "C" {
 #define EXTERN extern
 #endif
 
-EXTERN pid_t wait(int *stat_loc);
-EXTERN int   waitid(idtype_t idtype, id_t id, siginfo_t *siginfo, int options);
-EXTERN pid_t waitpid(pid_t pid, int *stat_loc, int options);
+EXTERN pid_t wait(FAR int *stat_loc);
+EXTERN int   waitid(idtype_t idtype, id_t id, FAR siginfo_t *info, int options);
+EXTERN pid_t waitpid(pid_t pid, FAR int *stat_loc, int options);
 
 #undef EXTERN
 #if defined(__cplusplus)