Perl One Liners

Command line Perl scripts for various purposes, such as HTML processing. Many of the examples work on STDIN.

# Check whether Perl module is installed
perldoc modulename

# Print paths where Perl looks for modules
perl -e 'print join "\n", @INC'

# Search and replace globally, ignore case
perl -i.bak -pe 's|searchstring|replacement|gi' infile

# Lower case all letters of input
perl -pe 's/([A-Z])/lc $1/ge' infile

# Encode STDIN with HTML entities
perl -MHTML::Entities -pe 'encode_entities($_)' infile

# Encode specified characters from STDIN with HTML entities
perl -MHTML::Entities -pe 'encode_entities($_, "\200-\377")' infile

# Decode STDIN with HTML entities
perl -MHTML::Entities -pe 'decode_entities($_)' infile
# Strip one line comments and blank lines from scripts
perl -pe 's%\s*(?:#[^!]|//).*|^\s*$%%s;' infile

# Using module subroutines that are not exported by default
perl -MCGI=:standard -e 'print start_html, end_html'

# Path to Perl's copy of the Unicode character database:
perl -MConfig -le 'print "$Config{privlib}/unicore/NamesList.txt"'

# Learn more about Perl's command line options
perldoc perlrun