system(3S)             UNIX System V(C Development Set)              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(2).

      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(2)

      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 -1
      and sets errno.

















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