Convert strings of initial whitespace, consisting of at least two spaces and/or tabs, to tabs. Read from standard input if given no file or a file named -.
Convert all, not just initial, strings of spaces and tabs.
nums is a comma-separated list of integers that specify the placement of tab stops. If a single integer is provided, the tab stops are set to every integer spaces. By default, tab stops are eight spaces apart. With -t and --tabs, the list may be separated by whitespace instead of commas. This option implies -a.
Print help message and then exit.
Print the version number and then exit.