I am looking for a filter similar to UNIX grep. It should scan a stream of data for some regex and set the exit code accordingly, but it should still pass through the data stream unmodified. We might call it transparent grep, 'tgrep' for short.

Example: The shell command ls | tgrep 'regex' && echo 'found some matching file names' should print all my file names, and append the message in the end.

Would a perl one-liner do? I thought of something similar to this: perl -pe '$match||=/regex/; END {$?=!$match}'

Of course, we might nicely wrap this up in a script file passing arguments etc. Any ideas and comments to make this run, are welcome.

In reply to 'Transparent grep' by Anonymous Monk

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