libite
2.6.1
src
runbg.c
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/* Run a command in the background: fork() + usleep() + execvp()
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*
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* Copyright (c) 2023 Joachim Wiberg <troglobit@gmail.com>
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*
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* Permission to use, copy, modify, and/or distribute this software for any
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* purpose with or without fee is hereby granted, provided that the above
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* copyright notice and this permission notice appear in all copies.
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*
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* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
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* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
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* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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*/
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#include <errno.h>
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#include <sys/types.h>
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#include <sys/wait.h>
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#include <unistd.h>
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int
runbg
(
char
*
const
cmd[],
int
delay)
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{
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int
pid = fork();
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int
rc;
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if
(!pid) {
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int
fd, maxfd;
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if
(setsid() == -1)
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_exit(errno);
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/* reparent to init */
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pid = fork();
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if
(pid == -1)
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_exit(errno);
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if
(pid > 0)
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_exit(0);
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maxfd = sysconf(_SC_OPEN_MAX);
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if
(maxfd == -1)
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maxfd = 8192;
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for
(fd = 0; fd < maxfd; fd++)
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close(fd);
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usleep(delay);
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_exit(execvp(cmd[0], cmd));
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}
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if
(pid == -1)
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return
-1;
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if
(waitpid(pid, &rc, 0) == -1)
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return
-1;
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if
(WIFEXITED(rc)) {
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errno = WEXITSTATUS(rc);
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if
(errno)
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rc = -1;
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else
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rc = 0;
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}
else
if
(WIFSIGNALED(rc)) {
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errno = EINTR;
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rc = -1;
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}
else
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rc = -1;
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return
rc;
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}
runbg
int runbg(char *const cmd[], int delay)
Definition
runbg.c:46
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