Linux and Unix Shell Programming

10.11. Quick one-liners

Here’s a small collection of one-liners ([] means a space and [ ] means a tab).

's/\.$//g'	Delete all lines ending with a period
'-e /abcd/d'	Delete lines containing abcd
's /[][][]*/[]/g'	Delete two or more spaces and replace with a single space
's/^[][]*//g'	Delete one or more spaces at the beginning of a line
's/\.[][]*/[]/g'	Delete a full stop followed by two or more spaces and replace with a space
'/^$/d'	Delete all blank lines
's/^.//g'	Delete the first character
's/COL\( . . .\)//g'	Delete three characters following the letters COL
's/^\///g'	Delete the leading slash from a pathname
's/[]/[ ]/g'	Delete all spaces and replace with a tab
's/^[ ]//g'	Delete all tabs from the beginning of the line
's/[ ]*//g'	Delete ...