pete@escher.intel.com (Peter Johnson ~) (03/11/89)
I have recently come across a peculiar bug in csh and was wondering if it posed any security problems. If you try to use a : modifier on a environment variable, strange things happen. For example: % echo $SHELL:t /bin/csh:t % echo ${SHELL:t} Variable syntax. % ls /bin/cshls: Command not found This bug appears in Ultrix 2.2, 3.0, SunOS 4.0, BSD 4.3, AIX, AUX. The only system that I have used where it does not appear is UTS. Of course UTS chokes on it as well, but in a different way. -Pete Johnson Peter Johnson pete@smdvx1.intel.COM {amdcad,decwrl,hplabs,oliveb,pur-ee,qantel}!intelca!mipos3!pete
maart@cs.vu.nl (Maarten Litmaath) (03/15/89)
pete@escher.intel.com (Peter Johnson ~) writes:
\% echo $SHELL:t
\/bin/csh:t
Correct: according to the manual `:' modifiers don't work on environment
variables.
\% echo ${SHELL:t}
\Variable syntax.
Correct too: the string "SHELL:t" doesn't have the form of an environment
variable, namely "[_a-zA-Z][_a-zA-Z0-9]*".
\% ls
\/bin/cshls: Command not found
How's that famous record by Johnny Ray again? "Crying", wasn't it?
Anyway, you get the idea.
--
Those against Rushdie haven't |Maarten Litmaath @ VU Amsterdam:
learned anything from the Dark Ages. |maart@cs.vu.nl, mcvax!botter!maart