http://www.perlmonks.org?node_id=985983


in reply to sending hexadecimal data via telnet

Or use pack to transform arbitrary hexademical numbers into bytes. For example: 
$ echo -n deadbeef | perl -pe's/([[:xdigit:]]{2})/pack("H2",$1)/ge' | 
+xxd
0000000: dead beef                                ....

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Sorry if my advice was wrong.

In Section Seekers of Perl Wisdom