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Command substitution inside of a variable expression (AIX, KORN)

 
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Old 01-25-2013
Command substitution inside of a variable expression (AIX, KORN)
Hello all. This is my first post/question on this site.
I’m a new Systems Analyst with previous experience with BASH. Although now I'm using AIX, and I’m trying to get a feel for the Korn shell (for those of you that don’t know AIX only uses the KORN shell).
I hope I put this into the correct forum topic; if not I apologize!

I am trying to use a command substitution inside of a variable expression:

Code:
#!/usr/bin/ksh

Code:
cd ${1:-`pwd`}; pwd; ls -l

I want it to cd to a directory that is provided as an argument, if no directory is provided then i want cd to default to the current directory. Then: pwd; ls -l

It’s pretty straight forward. This works if a directory is provided; where I'm getting caught is that if no argument is provided cd goes to the home directory, as if :- didn't default to `pwd`. I have also tried:

Code:
cd ${1:-.}; pwd; ls -l



The pwd and ls –l part of the code works with no problem. Also to note: I was talking to a co-worker and they commented that due to working under AIX that perhaps it doesn’t support variable expressions. If that is the case then fine, now I know!

Thanks in advance for your help.

-SIdney
 
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