cat file | grep -e str1 -e str2

I'd think there are at least 10 different and reasonable versions of the above command possible in Perl, one would sth. read like:

 perl -ne 'print if /str1/ || /str2/' file
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Addendum: To use this under Windows, please replace the quotes, e.g.:

 C:\> perl -ne "print if /str1/ || /str2/" file
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Regards

mwa