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Full Discussion: Command substitution inside of a variable expression (AIX, KORN)
Top Forums Shell Programming and Scripting Command substitution inside of a variable expression (AIX, KORN) Post 302761151 by sydox on Friday 25th of January 2013 08:24:21 AM
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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set_color

set_color(1)							       fish							      set_color(1)

NAME

       set_color - set_color - set the terminal color

set_color - set the terminal color
   Synopsis
       set_color [-v --version] [-h --help] [-b --background COLOR] [COLOR]

   Description
       Change the foreground and/or background color of the terminal. COLOR is one of black, red, green, brown, yellow, blue, magenta, purple,
       cyan, white and normal.

       o -b, --background Set the background color

       o -c, --print-colors Prints a list of all valid color names

       o -h, --help Display help message and exit

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       Calling set_color normal will set the terminal color to whatever is the default color of the terminal.

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Version 1.23.1							  Sun Jan 8 2012						      set_color(1)
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