diff -up psmisc-22.6/src/pstree.c.overflow psmisc-22.6/src/pstree.c
--- psmisc-22.6/src/pstree.c.overflow	2008-04-14 12:53:07.000000000 +0200
+++ psmisc-22.6/src/pstree.c	2008-04-14 13:05:51.000000000 +0200
@@ -608,6 +608,7 @@ read_proc (void)
 		perror (path);
 		exit (1);
 	      }
+            memset(readbuf, '\0', BUFSIZ + 1);
             fread(readbuf, BUFSIZ, 1, file) ;
             if (ferror(file) == 0) 
             {