SYSTEM(3)

NAME

     system -- pass a command to the shell

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <stdlib.h>

     int
     system(const char *string);

DESCRIPTION

     The system() function hands the argument string to the command inter-
     preter sh(1).  The calling process waits for the shell to finish execut-
     ing the command, ignoring SIGINT and SIGQUIT, and blocking SIGCHLD.

     If string is a NULL pointer, system() will return non-zero if the command
     interpreter sh(1) is available, and zero if it is not.

     The system() function returns the exit status of the shell as returned by
     waitpid(2), or -1 if an error occurred when invoking fork(2) or
     waitpid(2).  A return value of 127 means the execution of the shell
     failed.

SEE ALSO

     sh(1), execve(2), fork(2), waitpid(2), popen(3)

STANDARDS

     The system() function conforms to ISO/IEC 9899:1990 (``ISO C90'') and is
     expected to be IEEE Std 1003.2 (``POSIX.2'') compatible.