Perl one liners that can come in handy

This statement will modify "file.txt" by performing a search and replace and creating a backup of the original file called "file.txt.bak". The code below are formated for windows with double quotes ex: "/,//g", Linux uses single quotes ex: '/,//g'.

# Find all comma's "," and replace them with nothing "".
perl -i.bak -pe "s/,//g" file.txt

# Change format of file from DOS to Unix
perl -i.bak -pe "s/\r$//g" file.txt

# Change the format of a file from Unix to DOS
perl -i.bak -pe "s/$/\r/g" file.txt