awk substitute shell variables

bash variables awk substitution
Dan-Simon Myrland picture Dan-Simon Myrland · Dec 17, 2013 · Viewed 10.8k times · Source

I am struggling with awk substitution, for some reason the following code does not substitute anything, it just prints the output unaltered. Can anyone see what I am missing here? Any help would be very much appreachiated! (PS! The $DOCPATH and $SITEPATH are shell variables, they work perfectly fine in my awk setup).

awk -v docpath="$DOCPATH" -v sitepath="$SITEPATH" '{ sub( /docpath/, sitepath ) } { print }'

Answer

devnull picture devnull · Dec 17, 2013

Saying:

sub( /docpath/, sitepath )

causes awk to replace the pattern docpath, not the variable docpath.

You need to say:

awk -v docpath="$DOCPATH" -v sitepath="$SITEPATH" '{sub(docpath, sitepath)}1' filename

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