In a shell script, I want to remove all duplicate elements from various PATH-like environment variables, preserving the original order of the elements. Here is what I have so far: 

#!/bin/sh
MYPATH="/abc/def:fred:bill g:jock:bill g:/abc/def:/abc/def"
echo "MYPATH ='$MYPATH'"
MYPATH=`perl -e'my%s;print join":",grep(!$s{$_}++,split(/:/,shift))' "
+$MYPATH"`
echo "MYPATH2='$MYPATH'"

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Though I'm fairly happy with that solution, if I've blundered or you can see a better Perl (or non-Perl) way to do it, please respond away. Because my Unix has become a bit rusty, I'm concerned I may be overlooking a "standard" Unix way to do this. (A quick google uncovered this awk path cleaner but I didn't find a standard Unix command for this).

In reply to Perl one-liner to remove duplicate entries from PATH by eyepopslikeamosquito

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