NAME

system — pass a command to the shell

LIBRARY

Standard C Library (libc, -lc)

SYNOPSIS

#include <stdlib.h>

int
system(const char *command);

DESCRIPTION

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

RETURN VALUES

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.