Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have a KSH script that exports an environment variable (export SOME_VAR=123)

After running the script my current shell is unaffected and echo $SOME_VAR produces nothing.

I tried running . myScript.ksh but got the following error:

.: Permission denied.

Permissions for . are drwxr-xr-x

Any idea? (I'm not root)

share|improve this question
What permissions does myScript.ksh have? Is it readable? (Using . name is the correct way, since a process cannot update its parent's environment, which is why running the script "as a script" did not work.) – grawity Aug 29 '11 at 13:18
The script's permissions are -rwxr-xr-x - and it runs when invoking it without . before it. Can it be related to the fact my shell is TCSH? – RonK Aug 29 '11 at 13:29
Yes, it could. (See answer below.) – grawity Aug 29 '11 at 13:34
up vote 3 down vote accepted

You are using tcsh as your shell:

  1. tcsh does not have a . command – only source.

    > source myScript.ksh

    In sh, ksh and bash shells, "." is a built-in command, unrelated to the "current directory" usage of "."

    In csh and tcsh, no such built-in exists (the equivalent is named "source"), and using . will attempt to execute a directory, hence the "Permission denied" error.

  2. tcsh is a csh derivative, and uses a very different syntax for setting environment variables:

    setenv SOME_VAR 123

    This matters because using ./source causes the file's contents be executed in the current shell, meaning they have to be valid tcsh syntax.

share|improve this answer
Thank you - so to summarize, I cannot do what I wanted with a KSH script executed in a TCSH shell, right? – RonK Aug 29 '11 at 14:31
@RonK: Right. If you want to change enviroment variables of your current shell, you have to use . or source, and for that you must use a script written specifically for your current shell. – grawity Aug 29 '11 at 16:10
@RonK: There is another possibility — write a script, in any language that outputs (echo's) the apropriate setenv lines, then tell tcsh to evaluate that script's output: eval `./myscript`; this is somewhat fragile, though — you have to be very careful with output quoting. – grawity Aug 29 '11 at 16:12

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.