diff --git a/man/pidof.8 b/man/pidof.8

index 276a93c..ac5f58a 100644

--- a/man/pidof.8

+++ b/man/pidof.8

@@ -24,6 +24,7 @@ pidof -- find the process ID of a running program.

 .RB [ \-c ]

 .RB [ \-n ]

 .RB [ \-x ]

+.RB [ \-m ]

 .RB [ \-o

 .IR omitpid[,omitpid..] ]

 .RB [ \-o

@@ -63,6 +64,11 @@ shells running the named scripts.

 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

 program, in other words the calling shell or shell script.

+.IP -m

+When used with -o, will also omit any processes that have the same

+argv[0] and argv[1] as any explicitly omitted process ids. This can be

+used to avoid multiple shell scripts concurrently calling pidof returning

+each other's pids.

 .SH "EXIT STATUS"

 .TP

 .B 0

diff --git a/src/killall5.c b/src/killall5.c

index 5937d98..e73885e 100644

--- a/src/killall5.c

+++ b/src/killall5.c

@@ -118,6 +118,7 @@ typedef struct _s_nfs

 /* List of processes. */

 PROC *plist;

+PROC *olist;

 /* List of processes to omit. */

 OMIT *omit;

@@ -345,6 +346,20 @@ static void clear_mnt(void)

 	}

 }

+static void clear_omit(void)

+{

+	OMIT *o;

+	PROC *p;

+	for (o = omit; o; o = omit) {

+		omit = omit->next;

+		free(o);

+	}

+	for (p = olist; p; p = olist) {

+		olist = olist->next;

+		free(p);

+	}

+}

+

 /*

  *     Check if path is ia shadow off a NFS partition.

  */

@@ -452,6 +467,7 @@ int readproc(int do_stat)

 	DIR		*dir;

 	FILE		*fp;

 	PROC		*p, *n;

+	OMIT		*o, *m;

 	struct dirent	*d;

 	struct stat	st;

 	char		path[PATH_MAX+1];

@@ -624,6 +640,17 @@ int readproc(int do_stat)

 		p->next = plist;

 		plist = p;

 		p->pid = pid;

+		/* Could be smarter, but it's a small list. */

+		m = omit;

+		for (o = omit; m; o = m) {

+			m = o->next;

+			if (o->pid == p->pid) {

+				n = (PROC*)xmalloc(sizeof(PROC));

+				*n = *p;

+				n->next = olist;

+				olist = n;

+			}

+		}

 	}

 	closedir(dir);

@@ -813,6 +840,26 @@ PIDQ_HEAD *pidof(char *prog)

 	return q;

 }

+int matches(PROC *o, PROC *p)

+{

+	int ret = 0;

+	char *oargv1, *pargv1;

+	if ((o->argv0 && p->argv0 && !strcmp(o->argv0,p->argv0))) {

+		if (o->argv1 && p->argv1) {

+			if ((oargv1 = canonicalize_file_name(o->argv1)) == NULL)

+				oargv1 = strdup(o->argv1);

+			if ((pargv1 = canonicalize_file_name(p->argv1)) == NULL)

+				pargv1 = strdup(p->argv1);

+			if (! strcmp(oargv1, pargv1)) {

+				ret = 1;

+			}

+			free(oargv1);

+			free(pargv1);

+		}

+	}

+	return ret;

+}

+

 /* Give usage message and exit. */

 void usage(void)

 {

@@ -845,6 +892,7 @@ void nsyslog(int pri, char *fmt, ...)

 #define PIDOF_SINGLE	0x01

 #define PIDOF_OMIT	0x02

 #define PIDOF_NETFS	0x04

+#define PIDOF_OMIT_OMIT_MATCHES	0x08

 /*

  *	Pidof functionality.

@@ -861,6 +909,7 @@ int main_pidof(int argc, char **argv)

 	struct stat	st;

 	char		tmp[512];

+	olist = (PROC*)0;

 	omit = (OMIT*)0;

 	nlist = (NFS*)0;

 	opterr = 0;

@@ -868,7 +917,7 @@ int main_pidof(int argc, char **argv)

 	if ((token = getenv("PIDOF_NETFS")) && (strcmp(token,"no") != 0))

 		flags |= PIDOF_NETFS;

-	while ((opt = getopt(argc,argv,"hco:sxn")) != EOF) switch (opt) {

+	while ((opt = getopt(argc,argv,"hcmo:sxn")) != EOF) switch (opt) {

 		case '?':

 			nsyslog(LOG_ERR,"invalid options on command line!\n");

 			closelog();

@@ -907,6 +956,9 @@ int main_pidof(int argc, char **argv)

 		case 'x':

 			scripts_too++;

 			break;

+		case 'm':

+			flags |= PIDOF_OMIT_OMIT_MATCHES;

+			break;

 		case 'n':

 			flags |= PIDOF_NETFS;

 			break;

@@ -938,10 +990,13 @@ int main_pidof(int argc, char **argv)

 			pid_t spid = 0;

 			while ((p = get_next_from_pid_q(q))) {

 				if ((flags & PIDOF_OMIT) && omit) {

-					OMIT * optr;

-					for (optr = omit; optr; optr = optr->next) {

+					PROC * optr;

+					for (optr = olist; optr; optr = optr->next) {

 						if (optr->pid == p->pid)

 							break;

+						if (flags & PIDOF_OMIT_OMIT_MATCHES)

+							if (matches(optr, p))

+								break;

 					}

 					/*

@@ -977,6 +1032,7 @@ int main_pidof(int argc, char **argv)

 	if (!first)

 		printf("\n");

+	clear_omit();

 	clear_mnt();

 	closelog();