cosmopolitan/libc/calls/getpid.c

55 lines
2.5 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ This program is free software; you can redistribute it and/or modify │
│ it under the terms of the GNU General Public License as published by │
│ the Free Software Foundation; version 2 of the License. │
│ │
│ This program is distributed in the hope that it will be useful, but │
│ WITHOUT ANY WARRANTY; without even the implied warranty of │
│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU │
│ General Public License for more details. │
│ │
│ You should have received a copy of the GNU General Public License │
│ along with this program; if not, write to the Free Software │
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
│ 02110-1301 USA │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/assert.h"
#include "libc/calls/calls.h"
#include "libc/calls/internal.h"
#include "libc/dce.h"
#include "libc/nt/process.h"
#include "libc/runtime/missioncritical.h"
#include "libc/runtime/runtime.h"
static int g_pid;
static void __updatepid(void) {
atfork(__updatepid, NULL);
g_pid = __getpid();
}
int __getpid(void) {
if (!IsWindows()) {
return GETPID();
} else {
return NtGetPid();
}
}
/**
* Returns process id.
* @asyncsignalsafe
*/
int getpid(void) {
static bool once;
if (!once) {
once = true;
__updatepid();
}
return g_pid;
}