Accepted patch from Mark Hindley which avoids clearing realpath information

in pidof when trying to find matching executables.

doc/Changelog

@@ -8,6 +8,8 @@ sysvinit (3.07) released; urgency=low
       In other words, "pidof /tmp/sleep" and "pidof /usr/bin/sleep" will return
       the same PIDs when /tmp/sleep is a symbolic link to /usr/bin/sleep.
     * Fixed memory initialization error in pidof. Fix provided by Markus Fischer.
+    * Accepted patch from Mark Hindle which avoids clearing realpath information
+      in pidof when trying to find matching executables.
 
 
 sysvinit (3.06) released; urgency=low

man/pidof.8

@@ -94,7 +94,7 @@ that it returns PIDs of running programs that happen to have the same name
 as the program you're after but are actually other programs. Note 
 that the executable name of running processes is calculated with
 .BR readlink (2),
-so symbolic links to executables will also match. However, symbolic links to symbolic links will not match.  
+so symbolic links to executables will also match.
 .PP
 Zombie processes or processes in disk sleep (states Z and D, respectively)
 are ignored, as attempts to access the stats of these will sometimes fail.

src/killall5.c

@@ -740,8 +740,8 @@ PIDQ_HEAD *pidof(char *prog)
 		return NULL;
 
 	/* Try to stat the executable. */
+	memset(real_path, 0, sizeof(real_path));
 	if ( (prog[0] == '/') && ( realpath(prog, real_path) ) ) {
-		memset(&real_path[0], 0, sizeof(real_path));
 		dostat++;
 	}