in the grep, you have a regex, with a rather strange looking pattern.

Ditto. Maybe you've confused shell globbing with regular expressions? Let's break this is down:

_*_.txt

"_*_" would mean, zero or more instances of "_", with a "_" following. Then "." matches any character.

If you want to match _one_.txt, _two_.txt, etc, you should use:

_.+?_\.txt

Which means: a "_" followed by one or more of anything, non-greedily (because + is followed by ?, but note ? has another meaning in regexps depending on context; non-greedy matching is important when you are looking for any number of anything, followed by something in particular), then "_." (notice the . is escaped with \ because . alone has a special meaning, see above) followed by "txt".

If you haven't yet: perlretut.

In reply to Re: read the whole folder files by halfcountplus
in thread read the whole folder files by perllearner007

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