system - pass a command to the shell
Standard C Library (libc, -lc)
#include <stdlib.h> int system(const char *string);
The system()
function hands the argument string to the command interpreter sh(1).
The calling process waits for the shell to finish executing 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.
The system()
function conforms to ISO/IEC 9899:1990 (“ISO C89”) and is expected to be IEEE Std 1003.2 (“POSIX.2”) compatible.