NAME
	  system - Executes a shell command

     LIBRARY
	  Standard C Library (libc.a)

     SYNOPSIS
	  #include <stdlib.h>
	  int system (
		  const	char *command );


     PARAMETERS
	  command   Specifies a	valid sh shell command.


     DESCRIPTION
	  The system() function	passes the command parameter to	the sh
	  command, which interprets command as a command and executes
	  it.

	  The system() function	invokes	the fork() function to create
	  a child process that in turn uses the	exec function to run
	  sh, which interprets the shell command contained in the com-
	  mand parameter.  The current process waits until the shell
	  has completed, then returns the exit status of the shell.
	  Note that the	system() function affects only the process(es)
	  that it created.

	  Beware that while waiting for	command	to finish executing,
	  the system() function	ignores	the SIGINT and SIGQUIT sig-
	  nals,	and blocks SIGCHLD.  If	this characteristic causes
	  your application to miss a signal that might have terminated
	  the application, you should have the application check the
	  system() function's return value and then perform the	opera-
	  tion that would have been executed if	the application	had
	  caught that signal.

     NOTES
	  AES Support Level:
			 Full use


     RETURN VALUES
	  The system() function	does not return	until its child	pro-
	  cess has terminated.

	  If the argument specified by the command parameter is	a null
	  pointer, the system()	function returns 1 only	if a command
	  processor is available.

	  If the argument is not a null	pointer, upon successful
	  completion, the system() function returns the	exit status of
	  the executed command in the format specified by the wait-
	  pid()	function (see the wait(2) function).  If the function
	  fails, such as when the child	process	cannot be created or
	  if the shell's exit status cannot be obtained, the system()
	  function returns a value of -1 and sets errno	to indicate
	  the error.  A	return value of	127 indicates that the shell
	  could	not be executed.

     ERRORS
	  If the system() function fails, errno	may be set to one of
	  the following	values:


	  [EAGAIN]  The	system-imposed limit on	the total number of
		    processes under execution system-wide
		    ({PROC_MAX}), or by	a single user ID
		    ({CHILD_MAX}), would be exceeded.

	  [EINTR]   The	system() function was interrupted by a signal
		    which was caught.

	  [ENOMEM]  There is not enough	space left for this process.


     RELATED INFORMATION
	  Functions: exec(2), exit(2), fork(2),	wait(2)

	  Commands: sh(1)