The -p switch on the command line tells perl to read one line at a time therefore the contents of $2 are always empty because there is nothing after the newline for it to match.    You need something like: 

perl -lpe'$\ = /^usmat/ ? " phani " : " raj\n"' p1

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In reply to Re: The regular expression in perl one liner not giving the expected output by jwkrahn
in thread The regular expression in perl one liner not giving the expected output by perladdict

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