Circumvent the sed backreference limit \1 through \9

regex shell sed backreference
Steve M picture Steve M · Nov 30, 2010 · Viewed 8.8k times · Source

The sed manual clearly states that the available backreferences available for the replacement string in a substitute are numbered \1 through \9. I'm trying to parse a log file that has 10 fields.

I have the regex formed for it but the tenth match (and anything after) isn't accessible.

Does anyone have an elegant way to circumvent this limitation in KSH (or any language that perhaps I can port to shell scripting)?

Answer

robert picture robert · Nov 30, 2010

Can you user perl -pe 's/(match)(str)/$2$1/g;' in place of sed? The way to circumvent the backreference limit is to use something other than sed.

Also, I suppose you could do your substitution in two steps, but I don't know your pattern so I can't help you out with how.

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