1 /* vi: set sw=4 ts=4: */
5 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
7 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
13 In Linux we have three ways to determine "process name":
14 1. /proc/PID/stat has "...(name)...", among other things. It's so-called "comm" field.
15 2. /proc/PID/cmdline's first NUL-terminated string. It's argv[0] from exec syscall.
16 3. /proc/PID/exe symlink. Points to the running executable file.
24 comm: first 15 chars of base name
25 (if executable is a symlink, then first 15 chars of symlink name are used)
26 cmdline: argv[0] from exec syscall
27 exe: points to executable (resolves symlink, unlike comm)
29 script (an executable with #!/path/to/interpreter):
30 comm: first 15 chars of script's base name (symlinks are not resolved)
31 cmdline: /path/to/interpreter (symlinks are not resolved)
32 (script name is in argv[1], args are pushed into argv[2] etc)
33 exe: points to interpreter's executable (symlinks are resolved)
35 If FEATURE_PREFER_APPLETS=y (and more so if FEATURE_SH_STANDALONE=y),
36 some commands started from busybox shell, xargs or find are started by
37 execXXX("/proc/self/exe", applet_name, params....)
38 and therefore comm field contains "exe".
43 * Modified by Vladimir Oleynik for use with libbb/procps.c
44 * This finds the pid of the specified process.
45 * Currently, it's implemented by rummaging through
46 * the proc filesystem.
48 * Returns a list of all matching PIDs
49 * It is the caller's duty to free the returned pidlist.
51 pid_t* FAST_FUNC find_pid_by_name(const char* procName)
55 procps_status_t* p = NULL;
57 pidList = xmalloc(sizeof(*pidList));
58 while ((p = procps_scan(p, PSSCAN_PID|PSSCAN_COMM|PSSCAN_ARGV0))) {
60 /* we require comm to match and to not be truncated */
61 /* in Linux, if comm is 15 chars, it may be a truncated
62 * name, so we don't allow that to match */
63 (!p->comm[sizeof(p->comm)-2] && strcmp(p->comm, procName) == 0)
64 /* or we require argv0 to match (essential for matching reexeced /proc/self/exe)*/
65 || (p->argv0 && strcmp(bb_basename(p->argv0), procName) == 0)
66 /* TOOD: we can also try /proc/NUM/exe link, do we want that? */
68 pidList = xrealloc(pidList, sizeof(*pidList) * (i+2));
69 pidList[i++] = p->pid;
77 pid_t* FAST_FUNC pidlist_reverse(pid_t *pidList)
85 for (j = 0; i > j; i--, j++) {
87 pidList[i] = pidList[j];