sys-utils: cleanup license lines, add SPDX

[thirdparty/util-linux.git] / sys-utils / setsid.c

diff --git a/sys-utils/setsid.c b/sys-utils/setsid.c
index bae97ff9bd3390f02e51804aee752c8cd4b95a8d..5ccfd0ff1214df427471a44bef3834dd10b91946 100644 (file)
--- a/sys-utils/setsid.c
+++ b/sys-utils/setsid.c
@@ -1,7 +1,10 @@
 /*
+ * No copyright is claimed.  This code is in the public domain; do with
+ * it what you wish.
+ *
+ * Written by Rick Sladkey <jrs@world.std.com>
+ *
  * setsid.c -- execute a command in a new session
- * Rick Sladkey <jrs@world.std.com>
- * In the public domain.
  *
  * 1999-02-22 Arkadiusz Miśkiewicz <misiek@pld.ORG.PL>
  * - added Native Language Support
@@ -12,7 +15,6 @@
  * 2008-08-20 Daniel Kahn Gillmor <dkg@fifthhorseman.net>
  * - if forked, wait on child process and emit its return code.
  */
-
 #include <getopt.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -25,8 +27,9 @@
 #include "nls.h"
 #include "closestream.h"
 
-static void __attribute__ ((__noreturn__)) usage(FILE * out)
+static void __attribute__((__noreturn__)) usage(void)
 {
+       FILE *out = stdout;
        fputs(USAGE_HEADER, out);
        fprintf(out, _(
                " %s [options] <program> [arguments ...]\n"),
@@ -37,24 +40,25 @@ static void __attribute__ ((__noreturn__)) usage(FILE * out)
 
        fputs(USAGE_OPTIONS, out);
        fputs(_(" -c, --ctty     set the controlling terminal to the current one\n"), out);
+       fputs(_(" -f, --fork     always fork\n"), out);
        fputs(_(" -w, --wait     wait program to exit, and use the same return\n"), out);
 
-       fputs(USAGE_HELP, out);
-       fputs(USAGE_VERSION, out);
+       fprintf(out, USAGE_HELP_OPTIONS(16));
 
        fprintf(out, USAGE_MAN_TAIL("setsid(1)"));
-       exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
+       exit(EXIT_SUCCESS);
 }
 
 int main(int argc, char **argv)
 {
-       int ch;
+       int ch, forcefork = 0;
        int ctty = 0;
        pid_t pid;
        int status = 0;
 
        static const struct option longopts[] = {
                {"ctty", no_argument, NULL, 'c'},
+               {"fork", no_argument, NULL, 'f'},
                {"wait", no_argument, NULL, 'w'},
                {"version", no_argument, NULL, 'V'},
                {"help", no_argument, NULL, 'h'},
@@ -64,29 +68,34 @@ int main(int argc, char **argv)
        setlocale(LC_ALL, "");
        bindtextdomain(PACKAGE, LOCALEDIR);
        textdomain(PACKAGE);
-       atexit(close_stdout);
+       close_stdout_atexit();
 
-       while ((ch = getopt_long(argc, argv, "+Vhcw", longopts, NULL)) != -1)
+       while ((ch = getopt_long(argc, argv, "+Vhcfw", longopts, NULL)) != -1)
                switch (ch) {
-               case 'V':
-                       printf(UTIL_LINUX_VERSION);
-                       return EXIT_SUCCESS;
                case 'c':
                        ctty=1;
                        break;
+               case 'f':
+                       forcefork = 1;
+                       break;
                case 'w':
                        status = 1;
                        break;
+
                case 'h':
-                       usage(stdout);
+                       usage();
+               case 'V':
+                       print_version(EXIT_SUCCESS);
                default:
-                       usage(stderr);
+                       errtryhelp(EXIT_FAILURE);
                }
 
-       if (argc - optind < 1)
-               usage(stderr);
+       if (argc - optind < 1) {
+               warnx(_("no command specified"));
+               errtryhelp(EXIT_FAILURE);
+       }
 
-       if (getpgrp() == getpid()) {
+       if (forcefork || getpgrp() == getpid()) {
                pid = fork();
                switch (pid) {
                case -1:
@@ -112,5 +121,5 @@ int main(int argc, char **argv)
        if (ctty && ioctl(STDIN_FILENO, TIOCSCTTY, 1))
                err(EXIT_FAILURE, _("failed to set the controlling terminal"));
        execvp(argv[optind], argv + optind);
-       err(EXIT_FAILURE, _("failed to execute %s"), argv[optind]);
+       errexec(argv[optind]);
 }