Less is a command-line pager: a program that shows one page out of a file in a terminal window and shows more pages one at a time upon user request, irrespective of file size. Another noted similar program is more.
Less allows moving back and forth, supports arrow keys, and, when at the end of a pipeline, shows as much of the buffer as it can from the content fed into it, refreshing its buffer regularly as the pipeline provides more of the content.
- less --help
- Displays help in the less command itself. -h and -H do not output help.
- less --version
- less -V
- Outputs version.
- less -psearchterm MyFile.txt
- Option -p opens the files at the occurrences of the searchterm.
- grep dog AnimalData.txt | less
Keyboards commands that can be used once less is started:
- up and down arrow keys - scroll up or down
- page up or page down - as expected
- home - go to the top of the file
- end - go to the bottom of the file
- space - scroll forward
- q - quit
- h - help
- / - forward regex search
- n - next occurrence of a search match
- N - previous occurrence of a search match
- -i - ignore case in further searches
- less man page - section COMMANDS, freebsd.org
Versions of GNU less can be seen in http://ftp.gnu.org/gnu/less/.
Greenwood Software less versions can be seen in http://www.greenwoodsoftware.com/less/download.html and http://www.greenwoodsoftware.com/less/old.html.
Less is dual-licensed under GNU GPL V3+ and The Less License, a BSD-like license. It follows from README file from less-481.tar.gz GNU less distribution. The Less License is stated in the LICENSE file in the same distribution.