zhangzhebjut / linux-basic Goto Github PK

DESCRIPTION
       system()  executes a command specified in command by calling /bin/sh -c command,
       and returns after the command has been completed.  During execution of the  com-
       mand, SIGCHLD will be blocked, and SIGINT and SIGQUIT will be ignored.

RETURN VALUE
       The  value returned is -1 on error (e.g.  fork(2) failed), and the return status
       of the command otherwise.  This latter return status is in the format  specified
       in wait(2).  Thus, the exit code of the command will be WEXITSTATUS(status).  In
       case /bin/sh could not be executed, the exit status will be that  of  a  command
       that does exit(127).

       If  the  value  of  command  is  NULL, system() returns non-zero if the shell is
       available, and zero if not.

       system() does not affect the wait status of any other children.