Reading Perl documentation: perlrun

Recently I reread perlrun and found amazing things I didn't know about. Maybe this can be interesting for somebody else too.

Tracing Perl script

Something like set -x for bash scripts:

    PERLDB_OPTS="NonStop=1 AutoTrace=1 frame=2" perl -dS ./myscript.pl

Turn on Unicode

When printing Unicode text on the command line, you don't have to encode it, just use -C switch:

    perl -C -Mutf8 -e 'print "привет\n"'

-e can be used multiple times

    perl -e 'print "hello";' -e 'print "\n"'

Copy files with perl

If you can't use cp you can use perl!

    perl -p -i'/some/file/path/*' -e 1 file1 file2 file3

Extract Perl script

You received an email and there is a Perl script somewhere, you don't have to extract it yourself. Let perl do it. By using -x switch perl will try to find Perl script and will run it.

    Hi,

    here is a Perl script I wrote. Try it.

    #!/usr/bin/env perl

    print "Hello world\n";

And then:

    perl -x email.txt

Reading documentation is useful :)