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Top Forums Shell Programming and Scripting Understanding awk 'expansion' Post 302959232 by sea on Friday 30th of October 2015 11:54:37 AM
Old 10-30-2015
Understanding awk 'expansion'

Heyas

Recently i wanted to help someone with an awk script, but the end-script didnt work as expected.

He wanted, if HOME was empty, to get the HOME of the current USER from /etc/passwd.
At first i tried hardcoded with root:
Code:
awk -F: '/^root/ {print $6}' /etc/passwd

As that worked, i've added a variable, for the changeable 'current user'.
Code:
awk -v U=$(whoami) -F: '/^U/ {print $6}' /etc/passwd

But this didnt want to work, so in the end i had to:
Code:
cmd="awk -F:  '/^$(whoami)/ {print \$6}' /etc/passwd"
eval $cmd

Why is my 2nd code not working? (just returns empty)
Any (better) ideas?

Thank you
 

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IGAWK(1)							 Utility Commands							  IGAWK(1)

NAME
igawk - gawk with include files SYNOPSIS
igawk [ all gawk options ] -f program-file [ -- ] file ... igawk [ all gawk options ] [ -- ] program-text file ... DESCRIPTION
Igawk is a simple shell script that adds the ability to have ``include files'' to gawk(1). AWK programs for igawk are the same as for gawk, except that, in addition, you may have lines like @include getopt.awk in your program to include the file getopt.awk from either the current directory or one of the other directories in the search path. OPTIONS
See gawk(1) for a full description of the AWK language and the options that gawk supports. EXAMPLES
cat << EOF > test.awk @include getopt.awk BEGIN { while (getopt(ARGC, ARGV, "am:q") != -1) ... } EOF igawk -f test.awk SEE ALSO
gawk(1) Effective AWK Programming, Edition 1.0, published by the Free Software Foundation, 1995. AUTHOR
Arnold Robbins (arnold@skeeve.com). Free Software Foundation Nov 3 1999 IGAWK(1)
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