Peta::FFI::Libc#

📦 std

Call common libc functions from Perl without writing a single line of FFI glue.

Pre-baked libc bindings: each function here calls the C library directly, so there is no handle to open and no signature string to write. Reach for Peta::FFI when you need a function this module does not cover.

use Peta::FFI::Libc qw(getpid strlen strerror gethostname uname access R_OK);

print getpid() == $$ ? "getpid is \$\$\n" : "?\n";
print strlen("hello"), " ", strerror(2), "\n";   # 5 No such file or directory
my ($sys, $node) = uname();
print "$sys on $node\n" if gethostname() eq $node;
print access("/etc/passwd", R_OK) == 0 ? "readable\n" : "not readable: $!\n";

The functions keep C’s conventions: the ones that report success return 0 for it and -1 for failure, with $! set to the C errno. Nothing is exported by default; name what you want.

Function	Returns
`getpid`, `getppid`	the process id, the parent’s
`getuid`, `getgid`	the real user and group id
`geteuid`, `getegid`	the effective user and group id
`strlen($s)`	the length of `$s`; a NUL byte in it dies
`strerror($errno)`	the system’s message for an error number
`getenv($name)`	the value, or undef when unset
`setenv($name, $value, $over)`	0 / -1; `$over` false keeps an existing value
`unsetenv($name)`	0 / -1
`abs($n)`, `labs($n)`	the absolute value, as an int / a long
`sleep($s)`, `usleep($us)`	seconds left unslept / 0 or -1
`gethostname()`	the host name
`uname()`	(sysname, nodename, release, version, machine)
`access($path, $mode)`	0 / -1, `$mode` an OR of `F_OK`, `R_OK`, `W_OK`, `X_OK`
`unlink`, `rmdir($path)`	0 / -1
`mkdir($path, $mode)`	0 / -1
`chmod($path, $mode)`	0 / -1
`chown($path, $uid, $gid)`	0 / -1
`time()`	seconds since the epoch
`clock()`	processor time used, in `CLOCKS_PER_SEC` units

Peta::FFI::Libc is pperl’s own module, version 0.2.0.