>>>>> "P" == Peter J Kernan <pete / narya.PHYS.cwru.edu> writes:

P> irb(main):001:0> $0
P> "\000V"

 Try this patch

pigeon% diff -u ruby.c~ ruby.c
--- ruby.c~     Wed Sep  5 08:52:17 2001
+++ ruby.c      Thu Nov  8 07:22:03 2001
@@ -895,6 +895,7 @@
       j.pst_command = s;
       pstat(PSTAT_SETCMD, j, i, 0, 0);
     }
+    rb_progname = rb_tainted_str_new(s, i);
 #elif defined(HAVE_SETPROCTITLE)
     setproctitle("%.*s", i, s);
     rb_progname = rb_tainted_str_new(s, i);
@@ -927,7 +928,6 @@
     }
     rb_progname = rb_tainted_str_new2(origargv[0]);
 #endif
-    rb_progname = rb_tainted_str_new(s, i);
 }
 
 void
pigeon% 

pigeon% irb
irb(main):001:0> $0
"irb"
irb(main):002:0> 
pigeon%


Guy Decoux