pidof: new option to show cmdline-less PIDs (kernel workers), empty input fixed

diff --git a/pidof.1 b/pidof.1
index 5e0c9938fbd934bd2e50fd12e197c37b89e268b9..5ed61cdd9b6b1c29d255356c8d4abfd756f488fd 100644 (file)
--- a/pidof.1
+++ b/pidof.1
@@ -45,6 +45,9 @@ the current root directory of processes they do not own.
 .IP \-x
 Scripts too - this causes the program to also return process id's of
 shells running the named scripts.
+.IP \-w
+Show also processes that do not have visible command line (e.g. kernel
+worker threads).
 .IP "-o \fIomitpid\fP"
 Tells \fIpidof\fP to omit processes with that process id. The special
 pid \fB%PPID\fP can be used to name the parent process of the \fIpidof\fP

diff --git a/pidof.c b/pidof.c
index 90ecb1321473299e69e0bb2f5e6164991ad93290..25824e938404760d36ae45b82695a65de963a90f 100644 (file)
--- a/pidof.c
+++ b/pidof.c
@@ -55,6 +55,8 @@ static char *program = NULL;
 static int opt_single_shot    = 0;  /* -s */
 static int opt_scripts_too    = 0;  /* -x */
 static int opt_rootdir_check  = 0;  /* -c */
+static int opt_with_workers   = 0;  /* -w */
+
 
 static char *pidof_root = NULL;
 
@@ -69,6 +71,7 @@ static int __attribute__ ((__noreturn__)) usage(int opt)
        fputs(_(" -s, --single-shot         return one PID only\n"), fp);
        fputs(_(" -c, --check-root          omit processes with different root\n"), fp);
        fputs(_(" -x                        also find shells running the named scripts\n"), fp);
+       fputs(_(" -w, --with-workers        show kernel workers too\n"), fp);
        fputs(_(" -o, --omit-pid <PID,...>  omit processes with PID\n"), fp);
        fputs(_(" -S, --separator SEP       use SEP as separator put between PIDs"), fp);
        fputs(USAGE_SEPARATOR, fp);
@@ -142,7 +145,6 @@ static void select_procs (void)
        static int size = 0;
        char *cmd_arg0, *cmd_arg0base;
        char *cmd_arg1, *cmd_arg1base;
-       char *stat_cmd;
        char *program_base;
        char *root_link;
        char *exe_link;
@@ -168,10 +170,9 @@ static void select_procs (void)
                        }
                }
 
-               if (!is_omitted(task.XXXID)) {
+               if (!is_omitted(task.XXXID) && ((task.cmdline && *task.cmdline) || opt_with_workers)) {
 
                        cmd_arg0 = (task.cmdline && *task.cmdline) ? *task.cmdline : "\0";
-                       stat_cmd = task.cmd ? task.cmd : "\0";
 
                        /* processes starting with '-' are login shells */
                        if (*cmd_arg0 == '-') {
@@ -193,7 +194,7 @@ static void select_procs (void)
                            !strcmp(program_base, cmd_arg0) ||
                            !strcmp(program, cmd_arg0) ||
 
-                           !strcmp(program, stat_cmd) ||
+                           (opt_with_workers && !strcmp(program, task.cmd)) ||
 
                            !strcmp(program, exe_link_base) ||
                            !strcmp(program, exe_link))
@@ -293,13 +294,14 @@ int main (int argc, char **argv)
        int first_pid = 1;
 
        const char *separator = " ";
-       const char *opts = "scdnxmo:S:?Vh";
+       const char *opts = "scnxwmo:S:?Vh";
 
        static const struct option longopts[] = {
                {"check-root", no_argument, NULL, 'c'},
                {"single-shot", no_argument, NULL, 's'},
                {"omit-pid", required_argument, NULL, 'o'},
                {"separator", required_argument, NULL, 'S'},
+               {"with-workers", no_argument, NULL, 'w'},
                {"help", no_argument, NULL, 'h'},
                {"version", no_argument, NULL, 'V'},
                {NULL, 0, NULL, 0}
@@ -325,6 +327,9 @@ int main (int argc, char **argv)
                case 'x':
                        opt_scripts_too = 1;
                        break;
+               case 'w':
+                       opt_with_workers = 1;
+                       break;
                case 'c':
                        if (geteuid() == 0) {
                                opt_rootdir_check = 1;
@@ -359,6 +364,8 @@ int main (int argc, char **argv)
 
                program = argv[optind++];
 
+               if (*program == '\0') continue;
+
                select_procs(); /* get the list of matching processes */
 
                if (proc_count) {