system(3S)          (C Programming Language Utilities)           system(3S)


   NAME
         system - issue a shell command

   SYNOPSIS
         #include <stdlib.h>

         int system (const char *string);

   DESCRIPTION
         system causes the string to be given to the shell [see sh(1)] as
         input, as if the string had been typed as a command at a terminal.
         The current process waits until the shell has completed, then returns
         the exit status of the shell in the format specified by waitpid.

         If string is a NULL pointer, system checks if /sbin/sh exists and is
         executable.  If /sbin/sh is available, system returns non-zero;
         otherwise it returns zero.

         system fails if one or more of the following are true:

         EAGAIN      The system-imposed limit on the total number of processes
                     under execution by a single user would be exceeded.

         EINTR       system was interrupted by a signal.

         ENOMEM      The new process requires more memory than is allowed by
                     the system-imposed maximum MAXMEM.

   SEE ALSO
         exec(2), waitpid(3C).
         sh(1) in the User's Reference Manual.

   DIAGNOSTICS
         system forks to create a child process that in turn execs /sbin/sh in
         order to execute string.  If the fork or exec fails, system returns a
         value of -1 and sets errno.

















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