FAQ: Can I write useful Perl programs on the command line?

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This message is one of several periodic postings to comp.lang.perl.misc
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3.25: Can I write useful Perl programs on the command line?

    Yes. Read the perlrun manpage for more information. Some examples
    follow. (These assume standard Unix shell quoting rules.)

        # sum first and last fields
        perl -lane 'print $F[0] + $F[-1]' *

        # identify text files
        perl -le 'for(@ARGV) {print if -f && -T _}' *

        # remove (most) comments from C program
        perl -0777 -pe 's{}gs' foo.c

        # make file a month younger than today, defeating reaper daemons
        perl -e '$X=24*60*60; utime(time(),time() + 30 * $X,@ARGV)' *

        # find first unused uid
        perl -le '$i++ while getpwuid($i); print $i'

        # display reasonable manpath
        echo $PATH | perl -nl -072 -e '

    OK, the last one was actually an Obfuscated Perl Contest entry. :-)


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