system(3S)              LIBRARY FUNCTIONS              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 com-
     mand 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 interupted 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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