SYSTEM(3) BSD Library Functions Manual SYSTEM(3)NAMEsystem — 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 com‐
mand interpreter is available, or zero if none is available. Otherwise,
system() returns the termination status of the shell in the format speci‐
fied by waitpid(2).
RETURN VALUES
If a child process cannot be created, or the termination status of the
shell cannot be obtained, system() returns -1 and sets errno to indicate
the error. If execution of the shell fails, system() returns the termi‐
nation status for a program that terminates with a call of exit(127).
SEE ALSOsh(1), execve(2), waitpid(2), popen(3), shquote(3)STANDARDS
The system() function conforms to ANSI X3.159-1989 (“ANSI C89”) and IEEE
Std 1003.2-1992 (“POSIX.2”).
CAVEATS
Never supply the system() function with a command containing any part of
an unsanitized user-supplied string. Shell meta-characters present will
be honored by the sh(1) command interpreter.
BSD August 2, 2007 BSD