apps/examples/system: Add a simple test of the system command. Fix the first bug discovered by the test.

examples/README.txt

@@ -1887,6 +1887,11 @@ examples/smp
   This is a simple test for SMP functionality.  It is basically just the
   pthread barrier test with some custom instrumentation.
 
+examples/system
+^^^^^^^^^^^^^^^
+
+  This is a simple test of the system() command.
+
 examples/tcpecho
 ^^^^^^^^^^^^^^^^
 

examples/system/.gitignore

@@ -0,0 +1,11 @@
+/Make.dep
+/.depend
+/.built
+/*.asm
+/*.obj
+/*.rel
+/*.lst
+/*.sym
+/*.adb
+/*.lib
+/*.src

examples/system/Kconfig

@@ -0,0 +1,30 @@
+#
+# For a description of the syntax of this configuration file,
+# see the file kconfig-language.txt in the NuttX tools repository.
+#
+
+config EXAMPLES_SYSTEM
+	bool "System() example"
+	default n
+	---help---
+		Enable the system() example
+
+if EXAMPLES_SYSTEM
+
+config EXAMPLES_SYSTEM_PROGNAME
+	string "Program name"
+	default "system"
+	depends on BUILD_KERNEL
+	---help---
+		This is the name of the program that will be use when the NSH ELF
+		program is installed.
+
+config EXAMPLES_SYSTEM_PRIORITY
+	int "System task priority"
+	default 100
+
+config EXAMPLES_SYSTEM_STACKSIZE
+	int "System stack size"
+	default 2048
+
+endif

examples/system/Make.defs

@@ -0,0 +1,39 @@
+############################################################################
+# apps/examples/system/Make.defs
+# Adds selected applications to apps/ build
+#
+#   Copyright (C) 2016 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.
+#
+############################################################################
+
+ifeq ($(CONFIG_EXAMPLES_SYSTEM),y)
+CONFIGURED_APPS += examples/system
+endif

examples/system/Makefile

@@ -0,0 +1,56 @@
+############################################################################
+# apps/examples/system/Makefile
+#
+#   Copyright (C) 2008, 2010-2013 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.
+#
+############################################################################
+
+-include $(TOPDIR)/Make.defs
+
+# system() built-in application info
+
+CONFIG_EXAMPLES_SYSTEM_PRIORITY ?= SCHED_PRIORITY_DEFAULT
+CONFIG_EXAMPLES_SYSTEM_STACKSIZE ?= 2048
+
+APPNAME = system
+PRIORITY = $(CONFIG_EXAMPLES_SYSTEM_PRIORITY)
+STACKSIZE = $(CONFIG_EXAMPLES_SYSTEM_STACKSIZE)
+
+# system() Example
+
+ASRCS =
+CSRCS =
+MAINSRC = system_main.c
+
+CONFIG_EXAMPLES_SYSTEM_PROGNAME ?= system$(EXEEXT)
+PROGNAME = $(CONFIG_EXAMPLES_SYSTEM_PROGNAME)
+
+include $(APPDIR)/Application.mk

examples/system/system_main.c

@@ -0,0 +1,59 @@
+/****************************************************************************
+ * examples/system/system_main.c
+ *
+ *   Copyright (C) 2016 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 <stdio.h>
+#include <stdlib.h>
+
+/****************************************************************************
+ * Name: system_main
+ ****************************************************************************/
+
+#ifdef CONFIG_BUILD_KERNEL
+int main(int argc, FAR char *argv[])
+#else
+int system_main(int argc, char *argv[])
+#endif
+{
+  printf("Calling system(\"ls -Rl /\")\n");
+  int ret = system("ls -Rl /");
+  printf("system returned: %d\n", ret);
+  return 0;
+}

system/system/system.c

@@ -72,7 +72,7 @@
 
 int system(FAR char *cmd)
 {
-  FAR char *nshargv[3];
+  FAR char *nshargv[2];
   int pid;
   int rc;
   int ret;
@@ -81,9 +81,8 @@ int system(FAR char *cmd)
 
   /* Spawn nsh_system() which will execute the command under the shell */
 
-  nshargv[0] = "system";
+  nshargv[0] = cmd;
-  nshargv[1] = cmd;
+  nshargv[1] = NULL;
-  nshargv[2] = NULL;
 
   pid = task_create("system", CONFIG_SYSTEM_SYSTEM_PRIORITY,
                     CONFIG_SYSTEM_SYSTEM_STACKSIZE, nsh_system,