1 /*-
2 * Copyright (c) 2017 The NetBSD Foundation, Inc.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to The NetBSD Foundation
6 * by Christos Zoulas.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
19 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
21 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27 * POSSIBILITY OF SUCH DAMAGE.
28 */
29
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <err.h>
33 #include <sys/sysctl.h>
34
35 static int
getprocpath(char * path,size_t len,pid_t pid)36 getprocpath(char *path, size_t len, pid_t pid)
37 {
38 const int name[] = {
39 CTL_KERN, KERN_PROC_ARGS, pid, KERN_PROC_PATHNAME,
40 };
41 return sysctl(name, __arraycount(name), path, &len, NULL, 0);
42 }
43
44 int
main(int argc,char * argv[])45 main(int argc, char *argv[])
46 {
47 if (argc != 2) {
48 fprintf(stderr, "Usage: %s <pid>\n", getprogname());
49 return EXIT_FAILURE;
50 }
51
52 char buf[MAXPATHLEN];
53 pid_t pid = atoi(argv[1]);
54
55 if (getprocpath(buf, sizeof(buf), pid) == -1)
56 err(EXIT_FAILURE, "sysctl: %d", pid);
57 printf("%s\n", buf);
58 return EXIT_SUCCESS;
59 }
60