It's a bit hard to tell exactly what you want to do (please use <code> tags when you enter something that needs to retain its format), but here is a guess that might set you on your way. It slurps the entire file up at once (which may not work if it is really huge), then removes single newlines embedded in the pattern and adds a leading newline. Naturally you may want to generalize this to work for other patterns: perl -e "undef $/;$_=<>;s/G\n?5\n?7/\nG57/g;print;" yourfile.txt

In reply to Re: How to look for patterns in a file and create a CR by Albannach
in thread How to look for patterns in a file and create a CR by juo

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