SYSTEM(3) |
FreeBSD Library Functions Manual |
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 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.
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.
STANDARDS
The
system() function conforms to ISO/IEC 9899:1990 (“ISO C90”) and is expected to be IEEE Std 1003.2 (“POSIX.2”) compatible.