Add support for a login script (in addition to the init script); Add logic so that a USB console session can connect and reconnect to the USB serial device

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5582 42af7a65-404d-4744-a932-0658087f49c3

11 files changed, 732 insertions, 215 deletions

diff --git a/apps/ChangeLog.txt b/apps/ChangeLog.txt
index 778f1fcf2..6a2c1d4c9 100644
--- a/apps/ChangeLog.txt
+++ b/apps/ChangeLog.txt
@@ -495,5 +495,10 @@
 	* apps/examples/nettest and poll:  Complete Kconfig files.
 	* apps/examples/ostest/waitpid.c:  Need to use WEXITSTATUS()
 	  to decode the correct exit status.
-	* system/usbmonitor:  A daemon that can be used to monitor USB
+	* apps/system/usbmonitor:  A daemon that can be used to monitor USB
 	  trace outpout.
+	* apps/nshlib/nsh_usbdev.c, nsh_consolemain.c, nsh_session.c, nsh_script.c:
+	  Add support for a login script.  The init.d/rcS script will be executed
+	  once when NSH starts; the .nshrc script will be executed for each session:
+	  Once for serial, once for each USB connection, once for each Telnet
+	  session.
diff --git a/apps/include/nsh.h b/apps/include/nsh.h
index 4b5a3cd31..8e469a555 100644
--- a/apps/include/nsh.h
+++ b/apps/include/nsh.h
@@ -1,7 +1,7 @@
 /****************************************************************************
  * apps/include/nsh.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
@@ -45,6 +45,31 @@
 /****************************************************************************
  * Pre-Processor Definitions
  ****************************************************************************/
+/* If a USB device is selected for the NSH console then we need to handle some
+ * special start-up conditions.
+ */
+
+#undef HAVE_USB_CONSOLE
+#if defined(CONFIG_USBDEV)
+
+/* Check for a PL2303 serial console.  Use console device "/dev/console". */
+
+#  if defined(CONFIG_PL2303) && defined(CONFIG_PL2303_CONSOLE)
+#    define HAVE_USB_CONSOLE 1
+
+/* Check for a CDC/ACM serial console.  Use console device "/dev/console". */
+
+#  elif defined(CONFIG_CDCACM) && defined(CONFIG_CDCACM_CONSOLE)
+#    define HAVE_USB_CONSOLE 1
+
+/* Check for a generic USB console.  In this case, the USB console device
+ * must be provided in CONFIG_NSH_CONDEV.
+ */
+
+#  elif defined(CONFIG_NSH_USBCONSOLE)
+#    define HAVE_USB_CONSOLE 1
+#  endif
+#endif
 
 #if CONFIG_RR_INTERVAL > 0
 # define SCHED_NSH SCHED_RR
@@ -58,7 +83,8 @@
 
 #ifdef __cplusplus
 #define EXTERN extern "C"
-extern "C" {
+extern "C" 
+{
 #else
 #define EXTERN extern
 #endif
@@ -83,35 +109,54 @@ extern "C" {
  *
  ****************************************************************************/
 
-EXTERN void nsh_initialize(void);
+void nsh_initialize(void);
 
 /****************************************************************************
  * Name: nsh_consolemain
  *
  * Description:
  *   This interfaces maybe to called or started with task_start to start a
- *   single an NSH instance that operates on stdin and stdout (/dev/console).
- *   This function does not return.
+ *   single an NSH instance that operates on stdin and stdout.  This
+ *   function does not return.
  *
+ *   This function handles generic /dev/console character devices, or 
+ *   special USB console devices.  The USB console requires some special
+ *   operations to handle the cases where the session is lost when the
+ *   USB device is unplugged and restarted when the USB device is plugged
+ *   in again.
+  *
  * Input Parameters:
- *   Standard task start-up arguements.  These are not used.  argc may be
+ *   Standard task start-up arguments.  These are not used.  argc may be
  *   zero and argv may be NULL.
  *
  * Returned Values:
  *   This function does not normally return.  exit() is usually called to
  *   terminate the NSH session.  This function will return in the event of
- *   an error.  In that case, a nonzero value is returned (1).
+ *   an error.  In that case, a nonzero value is returned (EXIT_FAILURE=1).
  *  
  ****************************************************************************/
 
-EXTERN int nsh_consolemain(int argc, char *argv[]);
+int nsh_consolemain(int argc, char *argv[]);
 
-/* nsh_telnetstart() starts a telnet daemon that will allow multiple
- * NSH connections via telnet.  This function returns immediately after
- * the daemon has been started.
- */
+/****************************************************************************
+ * Name: nsh_telnetstart
+ *
+ * Description:
+ *   nsh_telnetstart() starts the Telnet daemon that will allow multiple
+ *   NSH connections via Telnet.  This function returns immediately after
+ *   the daemon has been started.
+ *
+ * Input Parameters:
+ *   None.  All of the properties of the Telnet daemon are controlled by
+ *   NuttX configuration setting.
+ *
+ * Returned Values:
+ *   The task ID of the Telnet daemon was successfully started.  A negated
+ *   errno value will be returned on failure.
+ *  
+ ****************************************************************************/
 
-EXTERN int nsh_telnetstart(void);
+int nsh_telnetstart(void);
 
 #undef EXTERN
 #ifdef __cplusplus
diff --git a/apps/nshlib/Kconfig b/apps/nshlib/Kconfig
index 589476baf..92bc83cfd 100644
--- a/apps/nshlib/Kconfig
+++ b/apps/nshlib/Kconfig
@@ -292,6 +292,19 @@ config NSH_ROMFSETC
 endif
 
 if NSH_ROMFSETC
+
+config NSH_ROMFSRC
+	bool "Support ROMFS login script"
+	default n
+	---help---
+		The ROMFS start-up script will be executed excactly once.  For
+		simple, persistence consoles (like a serial console).  But with
+		other other kinds of consoles, there may be multiple, transient
+		sessions (such as Telnet and USB consoles).  In these cases, you
+		may need another script that is executed at the beginning of each
+		session.  Selecting this option enables support for such a login
+		script
+
 config NSH_ROMFSMOUNTPT
 	string "ROMFS mount point"
 	default "/etc"
@@ -308,6 +321,15 @@ config NSH_INITSCRIPT
 		The default is init.d/rcS.  This is a relative path and must not
 		start with '/'.
 
+config NSH_RCSCRIPT
+	string "Relative path to login script"
+	default ".nshrc"
+	depends on NSH_ROMFSRC
+	---help---
+		This is the relative path to the login script within the mountpoint.
+		The default is .nshrc.  This is a relative path and must not
+		start with '/'.
+
 config NSH_ROMFSDEVNO
 	int "ROMFS block device minor number"
 	default 0
diff --git a/apps/nshlib/Makefile b/apps/nshlib/Makefile
index 948f43d52..76cdac40d 100644
--- a/apps/nshlib/Makefile
+++ b/apps/nshlib/Makefile
@@ -1,7 +1,7 @@
 ############################################################################
 # apps/nshlib/Makefile
 #
-#   Copyright (C) 2011-2012 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
@@ -39,9 +39,10 @@ include $(APPDIR)/Make.defs
 
 # NSH Library
 
-ASRCS =
-CSRCS = nsh_init.c nsh_parse.c nsh_console.c nsh_fscmds.c nsh_ddcmd.c \
-		nsh_proccmds.c nsh_mmcmds.c nsh_envcmds.c nsh_dbgcmds.c
+ASRCS  =
+CSRCS  = nsh_init.c nsh_parse.c nsh_console.c nsh_script.c nsh_session.c
+CSRCS += nsh_fscmds.c nsh_ddcmd.c nsh_proccmds.c nsh_mmcmds.c nsh_envcmds.c
+CSRCS += nsh_dbgcmds.c
 
 ifeq ($(CONFIG_NSH_BUILTIN_APPS),y)
 CSRCS += nsh_builtin.c
diff --git a/apps/nshlib/nsh.h b/apps/nshlib/nsh.h
index 168503580..23209dba5 100644
--- a/apps/nshlib/nsh.h
+++ b/apps/nshlib/nsh.h
@@ -93,8 +93,8 @@
 #  elif defined(CONFIG_CDCACM) && defined(CONFIG_CDCACM_CONSOLE)
 #    define HAVE_USB_CONSOLE 1
 
-/* Check for other USB console.  USB console device must be provided in
- * CONFIG_NSH_CONDEV.
+/* Check for a generic USB console.  In this case, the USB console device
+ * must be provided in CONFIG_NSH_CONDEV.
  */
 
 #  elif defined(CONFIG_NSH_USBCONSOLE)
@@ -244,40 +244,59 @@
 #    error "Mountpoint support is disabled"
 #    undef CONFIG_NSH_ROMFSETC
 #  endif
+
 #  if CONFIG_NFILE_DESCRIPTORS < 4
 #    error "Not enough file descriptors"
 #    undef CONFIG_NSH_ROMFSETC
 #  endif
+
 #  ifndef CONFIG_FS_ROMFS
 #    error "ROMFS support not enabled"
 #    undef CONFIG_NSH_ROMFSETC
 #  endif
+
 #  ifndef CONFIG_NSH_ROMFSMOUNTPT
 #    define CONFIG_NSH_ROMFSMOUNTPT "/etc"
 #  endif
-#  ifdef CONFIG_NSH_INIT
-#    ifndef CONFIG_NSH_INITSCRIPT
-#      define CONFIG_NSH_INITSCRIPT "init.d/rcS"
-#    endif
+
+#  ifndef CONFIG_NSH_INITSCRIPT
+#    define CONFIG_NSH_INITSCRIPT "init.d/rcS"
 #  endif
+
 #  undef NSH_INITPATH
 #  define NSH_INITPATH CONFIG_NSH_ROMFSMOUNTPT "/" CONFIG_NSH_INITSCRIPT
+
+#  ifdef CONFIG_NSH_ROMFSRC
+#    ifndef CONFIG_NSH_RCSCRIPT
+#      define CONFIG_NSH_RCSCRIPT ".nshrc"
+#    endif
+
+#    undef NSH_RCPATH
+#    define NSH_RCPATH CONFIG_NSH_ROMFSMOUNTPT "/" CONFIG_NSH_RCSCRIPT
+#  endif
+
 #  ifndef CONFIG_NSH_ROMFSDEVNO
 #    define CONFIG_NSH_ROMFSDEVNO 0
 #  endif
+
 #  ifndef CONFIG_NSH_ROMFSSECTSIZE
 #    define CONFIG_NSH_ROMFSSECTSIZE 64
 #  endif
+
 #  define NSECTORS(b)        (((b)+CONFIG_NSH_ROMFSSECTSIZE-1)/CONFIG_NSH_ROMFSSECTSIZE)
 #  define STR_RAMDEVNO(m)    #m
 #  define MKMOUNT_DEVNAME(m) "/dev/ram" STR_RAMDEVNO(m)
 #  define MOUNT_DEVNAME      MKMOUNT_DEVNAME(CONFIG_NSH_ROMFSDEVNO)
+
 #else
+
+#  undef CONFIG_NSH_ROMFSRC
 #  undef CONFIG_NSH_ROMFSMOUNTPT
-#  undef CONFIG_NSH_INIT
 #  undef CONFIG_NSH_INITSCRIPT
+#  undef CONFIG_NSH_RCSCRIPT
 #  undef CONFIG_NSH_ROMFSDEVNO
 #  undef CONFIG_NSH_ROMFSSECTSIZE
+
 #endif
 
 /* This is the maximum number of arguments that will be accepted for a
@@ -486,6 +505,12 @@ int nsh_usbconsole(void);
 
 #if CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_NFILE_STREAMS > 0 && !defined(CONFIG_NSH_DISABLESCRIPT)
 int nsh_script(FAR struct nsh_vtbl_s *vtbl, const char *cmd, const char *path);
+#ifdef CONFIG_NSH_ROMFSETC
+int nsh_initscript(FAR struct nsh_vtbl_s *vtbl);
+#ifdef CONFIG_NSH_ROMFSRC
+int nsh_loginscript(FAR struct nsh_vtbl_s *vtbl);
+#endif
+#endif
 #endif
 
 /* Architecture-specific initialization */
@@ -496,8 +521,10 @@ int nsh_archinitialize(void);
 #  define nsh_archinitialize() (-ENOSYS)
 #endif
 
-/* Message handler */
+/* Basic session and message handling */
 
+struct console_stdio_s;
+int nsh_session(FAR struct console_stdio_s *pstate);
 int nsh_parse(FAR struct nsh_vtbl_s *vtbl, char *cmdline);
 
 /* Application interface */
@@ -527,10 +554,8 @@ void nsh_dumpbuffer(FAR struct nsh_vtbl_s *vtbl, const char *msg,
 
 /* USB debug support */
 
-#if defined(CONFIG_NSH_USBDEV_TRACE) && defined(HAVE_USB_CONSOLE)
+#ifdef CONFIG_NSH_USBDEV_TRACE
 void nsh_usbtrace(void);
-#else
-#  define nsh_usbtrace()
 #endif
 
 /* Shell command handlers */
diff --git a/apps/nshlib/nsh_consolemain.c b/apps/nshlib/nsh_consolemain.c
index f05447a64..8be44f7aa 100644
--- a/apps/nshlib/nsh_consolemain.c
+++ b/apps/nshlib/nsh_consolemain.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * apps/nshlib/nsh_consolemain.c
  *
- *   Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2011-2013 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -47,6 +47,8 @@
 #include "nsh.h"
 #include "nsh_console.h"
 
+#ifndef HAVE_USB_CONSOLE
+
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
@@ -76,21 +78,25 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: nsh_consolemain
+ * Name: nsh_consolemain (Normal character device version)
  *
  * Description:
  *   This interfaces maybe to called or started with task_start to start a
- *   single an NSH instance that operates on stdin and stdout (/dev/console).
- *   This function does not return.
+ *   single an NSH instance that operates on stdin and stdout.  This
+ *   function does not normally return (see below).
  *
+ *   This version of nsh_consolmain handles generic /dev/console character
+ *   devices (see nsh_usbdev.c for another version for special USB console
+ *   devices).
+  *
  * Input Parameters:
- *   Standard task start-up arguements.  These are not used.  argc may be
+ *   Standard task start-up arguments.  These are not used.  argc may be
  *   zero and argv may be NULL.
  *
  * Returned Values:
  *   This function does not normally return.  exit() is usually called to
  *   terminate the NSH session.  This function will return in the event of
- *   an error.  In that case, a nonzero value is returned (1).
+ *   an error.  In that case, a nonzero value is returned (EXIT_FAILURE=1).
  *  
  ****************************************************************************/
 
@@ -101,70 +107,26 @@ int nsh_consolemain(int argc, char *argv[])
 
   DEBUGASSERT(pstate);
 
-  /* If we are using a USB serial console, then we will have to wait for the
-   * USB to be connected to the host.
-   */
-
-#ifdef HAVE_USB_CONSOLE
-  ret = nsh_usbconsole();
-  DEBUGASSERT(ret == OK);
-#endif
-
-  /* Present a greeting */
-
-  fputs(g_nshgreeting, pstate->cn_outstream);
-  fflush(pstate->cn_outstream);
-
-  /* Execute the startup script */
+  /* Execute the start-up script */
 
 #ifdef CONFIG_NSH_ROMFSETC
-  (void)nsh_script(&pstate->cn_vtbl, "init", NSH_INITPATH);
+  (void)nsh_initscript(&pstate->cn_vtbl);
 #endif
 
-  /* Then enter the command line parsing loop */
-
-  for (;;)
-    {
-      /* For the case of debugging the USB console... dump collected USB trace data */
+  /* Initialize any USB tracing options that were requested */
 
-      nsh_usbtrace();
-
-      /* Display the prompt string */
-
-      fputs(g_nshprompt, pstate->cn_outstream);
-      fflush(pstate->cn_outstream);
-
-      /* Get the next line of input */
-
-      ret = readline(pstate->cn_line, CONFIG_NSH_LINELEN,
-                     INSTREAM(pstate), OUTSTREAM(pstate));
-      if (ret > 0)
-        {
-          /* Parse process the command */
-
-          (void)nsh_parse(&pstate->cn_vtbl, pstate->cn_line);
-          fflush(pstate->cn_outstream);
-        }
+#ifdef CONFIG_NSH_USBDEV_TRACE
+  usbtrace_enable(TRACE_BITSET);
+#endif
 
-      /* Readline normally returns the number of characters read,
-       * but will return 0 on end of file or a negative value
-       * if an error occurs.  Either will cause the session to
-       * terminate.
-       */
+  /* Execute the session */
 
-      else
-        {
-          fprintf(pstate->cn_outstream, g_fmtcmdfailed, "nsh_consolemain", 
-                  "readline", NSH_ERRNO_OF(-ret));
-          nsh_exit(&pstate->cn_vtbl, 1);
-        }
-    }
+  ret = nsh_session(pstate);
 
-  /* Clean up.  We do not get here, but this is necessary to keep some
-   * compilers happy.  But others will complain that this code is not
-   * reachable.
-   */
+  /* Exit upon return */
 
-  nsh_exit(&pstate->cn_vtbl, 0);
-  return OK;
+  nsh_exit(&pstate->cn_vtbl, ret);
+  return ret;
 }
+
+#endif /* !HAVE_USB_CONSOLE */
diff --git a/apps/nshlib/nsh_fscmds.c b/apps/nshlib/nsh_fscmds.c
index 1a9f2eb57..f47dca896 100644
--- a/apps/nshlib/nsh_fscmds.c
+++ b/apps/nshlib/nsh_fscmds.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * apps/nshlib/nsh_fscmds.c
  *
- *   Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2011-2013 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -1221,71 +1221,6 @@ int cmd_rmdir(FAR struct nsh_vtbl_s *vtbl, int argc, char **argv)
 #endif
 
 /****************************************************************************
- * Name: nsh_script
- ****************************************************************************/
-
-#if  CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_NFILE_STREAMS > 0 && !defined(CONFIG_NSH_DISABLESCRIPT)
-int nsh_script(FAR struct nsh_vtbl_s *vtbl, const char *cmd, const char *path)
-{
-  char *fullpath;
-  FILE *stream;
-  char *buffer;
-  char *pret;
-  int ret = ERROR;
-
-  /* The path to the script may be relative to the current working directory */
-
-  fullpath = nsh_getfullpath(vtbl, path);
-  if (!fullpath)
-    {
-      return ERROR;
-    }
-
-  /* Get a reference to the common input buffer */
-
-  buffer = nsh_linebuffer(vtbl);
-  if (buffer)
-    {
-      /* Open the file containing the script */
-
-      stream = fopen(fullpath, "r");
-      if (!stream)
-        {
-          nsh_output(vtbl, g_fmtcmdfailed, cmd, "fopen", NSH_ERRNO);
-          nsh_freefullpath(fullpath);
-          return ERROR;
-        }
-
-      /* Loop, processing each command line in the script file (or
-       * until an error occurs)
-       */
-
-      do
-        {
-          /* Get the next line of input from the file */
-
-          fflush(stdout);
-          pret = fgets(buffer, CONFIG_NSH_LINELEN, stream);
-          if (pret)
-            {
-              /* Parse process the command.  NOTE:  this is recursive...
-               * we got to cmd_sh via a call to nsh_parse.  So some
-               * considerable amount of stack may be used.
-               */
-
-              ret = nsh_parse(vtbl, buffer);
-            }
-        }
-      while (pret && ret == OK);
-      fclose(stream);
-    }
-
-  nsh_freefullpath(fullpath);
-  return ret;
-}
-#endif
-
-/****************************************************************************
  * Name: cmd_sh
  ****************************************************************************/
 
diff --git a/apps/nshlib/nsh_script.c b/apps/nshlib/nsh_script.c
new file mode 100644
index 000000000..3aa698b31
--- /dev/null
+++ b/apps/nshlib/nsh_script.c
@@ -0,0 +1,195 @@
+/****************************************************************************
+ * apps/nshlib/nsh_script.c
+ *
+ *   Copyright (C) 2007-2009, 2011-2013 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include "nsh.h"
+#include "nsh_console.h"
+
+#if  CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_NFILE_STREAMS > 0 && !defined(CONFIG_NSH_DISABLESCRIPT)
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nsh_script
+ *
+ * Description:
+ *   Execute the NSH script at path.
+ *
+ ****************************************************************************/
+
+int nsh_script(FAR struct nsh_vtbl_s *vtbl, FAR const char *cmd,
+               FAR const char *path)
+{
+  char *fullpath;
+  FILE *stream;
+  char *buffer;
+  char *pret;
+  int ret = ERROR;
+
+  /* The path to the script may be relative to the current working directory */
+
+  fullpath = nsh_getfullpath(vtbl, path);
+  if (!fullpath)
+    {
+      return ERROR;
+    }
+
+  /* Get a reference to the common input buffer */
+
+  buffer = nsh_linebuffer(vtbl);
+  if (buffer)
+    {
+      /* Open the file containing the script */
+
+      stream = fopen(fullpath, "r");
+      if (!stream)
+        {
+          nsh_output(vtbl, g_fmtcmdfailed, cmd, "fopen", NSH_ERRNO);
+          nsh_freefullpath(fullpath);
+          return ERROR;
+        }
+
+      /* Loop, processing each command line in the script file (or
+       * until an error occurs)
+       */
+
+      do
+        {
+          /* Get the next line of input from the file */
+
+          fflush(stdout);
+          pret = fgets(buffer, CONFIG_NSH_LINELEN, stream);
+          if (pret)
+            {
+              /* Parse process the command.  NOTE:  this is recursive...
+               * we got to cmd_sh via a call to nsh_parse.  So some
+               * considerable amount of stack may be used.
+               */
+
+              ret = nsh_parse(vtbl, buffer);
+            }
+        }
+      while (pret && ret == OK);
+      fclose(stream);
+    }
+
+  nsh_freefullpath(fullpath);
+  return ret;
+}
+
+/****************************************************************************
+ * Name: nsh_initscript
+ *
+ * Description:
+ *   Attempt to execute the configured initialization script.  This script
+ *   should be executed once when NSH starts.  nsh_initscript is idempotent
+ *   and may, however, be called multiple times (the script will be executed
+ *   once.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_NSH_ROMFSETC
+int nsh_initscript(FAR struct nsh_vtbl_s *vtbl)
+{
+  static bool initialized;
+  bool already;
+  int ret = OK;
+
+  /* Atomic test and set of the initialized flag */
+
+  sched_lock();
+  already     = initialized;
+  initialized = true;
+  sched_unlock();
+
+  /* If we have not already executed the init script, then do so now */
+
+  if (!already)
+    {
+      ret = nsh_script(vtbl, "init", NSH_INITPATH);
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: nsh_loginscript
+ *
+ * Description:
+ *   Attempt to execute the configured login script.  This script
+ *   should be executed when each NSH session starts.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_NSH_ROMFSRC
+int nsh_loginscript(FAR struct nsh_vtbl_s *vtbl)
+{
+  return nsh_script(vtbl, "login", NSH_RCPATH);
+}
+#endif
+#endif /* CONFIG_NSH_ROMFSETC */
+
+#endif /* CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_NFILE_STREAMS > 0 && !CONFIG_NSH_DISABLESCRIPT */
diff --git a/apps/nshlib/nsh_session.c b/apps/nshlib/nsh_session.c
new file mode 100644
index 000000000..8079b2de5
--- /dev/null
+++ b/apps/nshlib/nsh_session.c
@@ -0,0 +1,163 @@
+/****************************************************************************
+ * apps/nshlib/nsh_session.c
+ *
+ *   Copyright (C) 2007-2009, 2011-2013 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <apps/readline.h>
+
+#include "nsh.h"
+#include "nsh_console.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nsh_session
+ *
+ * Description:
+ *   This is the common session logic or any NSH session.  This function
+ *   return when an error reading from the input stream occurs, presumably
+ *   signaling the end of the session.
+ *
+ *   This function:
+ *   - Executes the NSH logic script
+ *   - Presents a greeting
+ *   - Then provides a prompt then gets and processes the command line.
+ *   - This continues until an error occurs, then the session returns.
+ *
+ * Input Parameters:
+ *   pstate - Abstracts the underlying session.
+ *
+ * Returned Values:
+ *   EXIT_SUCESS or EXIT_FAILURE is returned.
+ *  
+ ****************************************************************************/
+
+int nsh_session(FAR struct console_stdio_s *pstate)
+{
+  int ret;
+
+  DEBUGASSERT(pstate);
+
+  /* Present a greeting */
+
+  fputs(g_nshgreeting, pstate->cn_outstream);
+  fflush(pstate->cn_outstream);
+
+  /* Execute the login script */
+
+#ifdef CONFIG_NSH_ROMFSRC
+  (void)nsh_loginscript(&pstate->cn_vtbl);
+#endif
+
+  /* Then enter the command line parsing loop */
+
+  for (;;)
+    {
+      /* For the case of debugging the USB console... dump collected USB trace data */
+
+#ifdef CONFIG_NSH_USBDEV_TRACE
+      nsh_usbtrace();
+#endif
+
+      /* Display the prompt string */
+
+      fputs(g_nshprompt, pstate->cn_outstream);
+      fflush(pstate->cn_outstream);
+
+      /* Get the next line of input */
+
+      ret = readline(pstate->cn_line, CONFIG_NSH_LINELEN,
+                     INSTREAM(pstate), OUTSTREAM(pstate));
+      if (ret > 0)
+        {
+          /* Parse process the command */
+
+          (void)nsh_parse(&pstate->cn_vtbl, pstate->cn_line);
+          fflush(pstate->cn_outstream);
+        }
+
+      /* Readline normally returns the number of characters read,
+       * but will return 0 on end of file or a negative value
+       * if an error occurs.  Either will cause the session to
+       * terminate.
+       */
+
+      else
+        {
+          fprintf(pstate->cn_outstream, g_fmtcmdfailed, "nsh_session", 
+                  "readline", NSH_ERRNO_OF(-ret));
+          return ret == 0 ? EXIT_SUCCESS : EXIT_FAILURE;
+        }
+    }
+
+  /* We do not get here, but this is necessary to keep some compilers happy.
+   * But others will complain that this code is not reachable.
+   */
+
+  return EXIT_SUCCESS;
+}
diff --git a/apps/nshlib/nsh_telnetd.c b/apps/nshlib/nsh_telnetd.c
index 478935d7f..76ed81086 100644
--- a/apps/nshlib/nsh_telnetd.c
+++ b/apps/nshlib/nsh_telnetd.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * apps/nshlib/nsh_telnetd.c
  *
- *   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
@@ -198,15 +198,29 @@ int nsh_telnetmain(int argc, char *argv[])
     }
 #endif /* CONFIG_NSH_TELNET_LOGIN */
 
+  /* The following logic mostly the same as the login in nsh_session.c.  It
+   * differs only in that gets() is called to get the command instead of
+   * readline().
+   */
+
   /* Present the NSH greeting */
 
   fputs(g_nshgreeting, pstate->cn_outstream);
   fflush(pstate->cn_outstream);
 
-  /* Execute the startup script */
+  /* Execute the startup script.  If standard console is also defined, then
+   * we will not bother with the initscript here (although it is safe to
+   * call nshinitscript multiple times).
+   */
 
 #if defined(CONFIG_NSH_ROMFSETC) && !defined(CONFIG_NSH_CONSOLE)
-  (void)nsh_script(&pstate->cn_vtbl, "init", NSH_INITPATH);
+  (void)nsh_initscript(&pstate->cn_vtbl);
+#endif
+
+  /* Execute the login script */
+
+#ifdef CONFIG_NSH_ROMFSRC
+  (void)nsh_loginscript(&pstate->cn_vtbl);
 #endif
 
   /* Then enter the command line parsing loop */
@@ -261,8 +275,8 @@ int nsh_telnetmain(int argc, char *argv[])
  *   NuttX configuration setting.
  *
  * Returned Values:
- *   Zero if the Telnet daemon was successfully started.  A negated errno
- *   value will be returned on failure.
+ *   The task ID of the Telnet daemon was successfully started.  A negated
+ *   errno value will be returned on failure.
  *  
  ****************************************************************************/
 
@@ -271,6 +285,15 @@ int nsh_telnetstart(void)
   struct telnetd_config_s config;
   int ret;
 
+  /* Initialize any USB tracing options that were requested.  If standard
+   * console is also defined, then we will defer this step to the standard
+   * console.
+   */
+
+#if defined(CONFIG_NSH_USBDEV_TRACE) && !defined(CONFIG_NSH_CONSOLE)
+  usbtrace_enable(TRACE_BITSET);
+#endif
+
   /* Configure the telnet daemon */
 
   config.d_port      = HTONS(CONFIG_NSH_TELNETD_PORT);
diff --git a/apps/nshlib/nsh_usbdev.c b/apps/nshlib/nsh_usbdev.c
index 2064cbd84..193fe0d79 100644
--- a/apps/nshlib/nsh_usbdev.c
+++ b/apps/nshlib/nsh_usbdev.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * apps/nshlib/nsh_usbdev.c
  *
- *   Copyright (C) 2012 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2012-2013 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -55,11 +55,10 @@
 #endif
 
 #include "nsh.h"
-
-#ifdef CONFIG_USBDEV
+#include "nsh_console.h"
 
 /****************************************************************************
- * Definitions
+ * Pre-processor Definitions
  ****************************************************************************/
 /* Output USB trace data to the console device using printf() unless (1)
  * debug is enabled, then we want to keep the trace output in sync with the
@@ -98,6 +97,14 @@
  * Name: nsh_tracecallback
  ****************************************************************************/
 
+/****************************************************************************
+ * Name: nsh_tracecallback
+ *
+ * Description:
+ *   This is part of the USB trace logic
+ *
+ ****************************************************************************/
+
 #ifdef CONFIG_NSH_USBDEV_TRACE
 static int nsh_tracecallback(struct usbtrace_s *trace, void *arg)
 {
@@ -107,27 +114,96 @@ static int nsh_tracecallback(struct usbtrace_s *trace, void *arg)
 #endif
 
 /****************************************************************************
- * Public Functions
+ * Name: nsh_configstdio
+ *
+ * Description:
+ *   Configure standard I/O
+ *
+ ****************************************************************************/
+
+#ifdef HAVE_USB_CONSOLE
+static void nsh_configstdio(int fd)
+{
+  /* Make sure the stdin, stdout, and stderr are closed */
+
+  (void)fclose(stdin);
+  (void)fclose(stdout);
+  (void)fclose(stderr);
+
+  /* Dup the fd to create standard fd 0-2 */
+
+  (void)dup2(fd, 0);
+  (void)dup2(fd, 1);
+  (void)dup2(fd, 2);
+
+  /* fdopen to get the stdin, stdout and stderr streams. The following logic depends
+   * on the fact that the library layer will allocate FILEs in order.  And since
+   * we closed stdin, stdout, and stderr above, that is what we should get.
+   *
+   * fd = 0 is stdin  (read-only)
+   * fd = 1 is stdout (write-only, append)
+   * fd = 2 is stderr (write-only, append)
+   */
+
+  (void)fdopen(0, "r");
+  (void)fdopen(1, "a");
+  (void)fdopen(2, "a");
+}
+#endif
+
+/****************************************************************************
+ * Name: nsh_nullstdio
+ *
+ * Description:
+ *   Use /dev/null for standard I/O
+ *
  ****************************************************************************/
 
+#ifdef HAVE_USB_CONSOLE
+static int nsh_nullstdio(void)
+{
+  int fd;
+
+  /* Open /dev/null for read/write access */
+
+  fd = open("/dev/null", O_RDWR);
+  if (fd >= 0)
+    {
+      /* Configure standard I/O to use /dev/null */
+
+      nsh_configstdio(fd);
+
+      /* We can close the original file descriptor now (unless it was one of
+       * 0-2)
+       */
+
+      if (fd > 2)
+       {
+          close(fd);
+       }
+
+      return OK;
+    }
+
+  return fd;
+}
+#endif
+
 /****************************************************************************
- * Name: nsh_usbconsole
+ * Name: nsh_waitusbready
+ *
+ * Description:
+ *   Wait for the USB console device to be ready
+ *
  ****************************************************************************/
 
 #ifdef HAVE_USB_CONSOLE
-int nsh_usbconsole(void)
+static int nsh_waitusbready(void)
 {
   char inch;
   ssize_t nbytes;
   int nlc;
   int fd;
-  int ret;
-
-  /* Initialize any USB tracing options that were requested */
-
-#ifdef CONFIG_NSH_USBDEV_TRACE
-  usbtrace_enable(TRACE_BITSET);
-#endif
 
   /* Don't start the NSH console until the console device is ready.  Chances
    * are, we get here with no functional console.  The USB console will not
@@ -135,17 +211,6 @@ int nsh_usbconsole(void)
    * host-side application opens the connection.
    */
 
-  /* Initialize the USB serial driver */
-
-#if defined(CONFIG_PL2303) || defined(CONFIG_CDCACM)
-#ifdef CONFIG_CDCACM
-  ret = cdcacm_initialize(CONFIG_NSH_USBDEV_MINOR, NULL);
-#else
-  ret = usbdev_serialinitialize(CONFIG_NSH_USBDEV_MINOR);
-#endif
-  DEBUGASSERT(ret == OK);
-#endif
-
   /* Open the USB serial device for read/write access */
 
   do
@@ -199,17 +264,9 @@ int nsh_usbconsole(void)
     }
   while (nlc < 3);
 
-  /* Make sure the stdin, stdout, and stderr are closed */
-
-  (void)fclose(stdin);
-  (void)fclose(stdout);
-  (void)fclose(stderr);
-
-  /* Dup the fd to create standard fd 0-2 */
+  /* Configure standard I/O */
 
-  (void)dup2(fd, 0);
-  (void)dup2(fd, 1);
-  (void)dup2(fd, 2);
+  nsh_configstdio(fd);
 
   /* We can close the original file descriptor now (unless it was one of 0-2) */
 
@@ -218,33 +275,117 @@ int nsh_usbconsole(void)
       close(fd);
     }
 
-  /* fdopen to get the stdin, stdout and stderr streams. The following logic depends
-   * on the fact that the library layer will allocate FILEs in order.  And since
-   * we closed stdin, stdout, and stderr above, that is what we should get.
-   *
-   * fd = 0 is stdin  (read-only)
-   * fd = 1 is stdout (write-only, append)
-   * fd = 2 is stderr (write-only, append)
-   */
-
-  (void)fdopen(0, "r");
-  (void)fdopen(1, "a");
-  (void)fdopen(2, "a");
-
   return OK;
 }
+#endif
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nsh_consolemain (USB console version)
+ *
+ * Description:
+ *   This interfaces maybe to called or started with task_start to start a
+ *   single an NSH instance that operates on stdin and stdout.  This
+ *   function does not return.
+ *
+ *   This function handles generic /dev/console character devices, or 
+ *   special USB console devices.  The USB console requires some special
+ *   operations to handle the cases where the session is lost when the
+ *   USB device is unplugged and restarted when the USB device is plugged
+ *   in again.
+  *
+ * Input Parameters:
+ *   Standard task start-up arguments.  These are not used.  argc may be
+ *   zero and argv may be NULL.
+ *
+ * Returned Values:
+ *   This function does not return nor does it ever exit (unless the user
+ *   executes the NSH exit command).
+ *  
+ ****************************************************************************/
+
+#ifdef HAVE_USB_CONSOLE
+int nsh_consolemain(int argc, char *argv[])
+{
+  FAR struct console_stdio_s *pstate = nsh_newconsole();
+  int ret;
 
-#endif /* HAVE_USB_CONSOLE */
+  DEBUGASSERT(pstate);
+
+  /* Initialize any USB tracing options that were requested */
+
+#ifdef CONFIG_NSH_USBDEV_TRACE
+  usbtrace_enable(TRACE_BITSET);
+#endif
+
+  /* Initialize the USB serial driver */
+
+#if defined(CONFIG_PL2303) || defined(CONFIG_CDCACM)
+#ifdef CONFIG_CDCACM
+  ret = cdcacm_initialize(CONFIG_NSH_USBDEV_MINOR, NULL);
+#else
+  ret = usbdev_serialinitialize(CONFIG_NSH_USBDEV_MINOR);
+#endif
+  DEBUGASSERT(ret == OK);
+#endif
+
+  /* Configure to use /dev/null if we do not have a valid console. */
+
+#ifndef CONFIG_DEV_CONSOLE
+  (void)nsh_nullstdio();
+#endif
+
+  /* Execute the one-time start-up script (output may go to /dev/null) */
+
+#ifdef CONFIG_NSH_ROMFSETC
+  (void)nsh_initscript(&pstate->cn_vtbl);
+#endif
+
+  /* Now loop, executing creating a session for each USB connection */
+
+  for (;;)
+    {
+      /* Wait for the USB to be connected to the host and switch
+       * standard I/O to the USB serial device.
+       */
+
+      ret = nsh_waitusbready();
+      DEBUGASSERT(ret == OK);
+
+      /* Execute the session */
+
+      (void)nsh_session(pstate);
+
+      /* Switch to /dev/null because we probably no longer have a
+       * valid console device.
+       */
+
+      (void)nsh_nullstdio();
+    }
+}
+#endif
 
 /****************************************************************************
  * Name: nsh_usbtrace
+ *
+ * Description:
+ *   The function is called from the nsh_session() to dump USB data to the
+ *   SYSLOG device.
+ *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Values:
+ *   None
+ *  
  ****************************************************************************/
 
-#if defined(CONFIG_NSH_USBDEV_TRACE) && defined(HAVE_USB_CONSOLE)
+#ifdef CONFIG_NSH_USBDEV_TRACE
 void nsh_usbtrace(void)
 {
   (void)usbtrace_enumerate(nsh_tracecallback, NULL);
 }
 #endif
-
-#endif /* CONFIG_USBDEV */