::  Posts  ::  RSS  ::  ◂◂RSS  ::  Contact

Colored grep

January 19th, 2009
shell, programming  [html]
I figured out some cool stuff I can do with colored grep. I often want to, when grepping, see the bit that matched in a different color. I knew grep --color would do this, but I'd wanted to be able to do this with multiple greps and multiple colors. Then I noticed the GREP_COLOR environment variable and the grep --color=always options. So I made the aliases:
alias grey-grep="GREP_COLOR='1;30' grep --color=always"
alias red-grep="GREP_COLOR='1;31' grep --color=always"
alias green-grep="GREP_COLOR='1;32' grep --color=always"
alias yellow-grep="GREP_COLOR='1;33' grep --color=always"
alias blue-grep="GREP_COLOR='1;34' grep --color=always"
alias magenta-grep="GREP_COLOR='1;35' grep --color=always"
alias cyan-grep="GREP_COLOR='1;36' grep --color=always"
alias white-grep="GREP_COLOR='1;37' grep --color=always"
These let me do things like:
user@host /path/to/cwd $ echo hello there | blue_grep ll | yellow_grep ere
hello there
The primary use for me is when I want to look for something and don't really know what it is yet. Often this will include wanting to find things that are near each other, but I'm not sure how near. The color helps immensely with visual grepping.

The main downside to this method is that I have to specify the color. What I really want to have is something where multiple calls to color grep in the same pipe automagically use different colors.

Update 2012-09-25: If you want to just highlight things in the output, you can run these with a -C 10000 argument. Or define some more commands:

alias highlight-grey="grey-grep -C 10000"
alias highlight-red="red-grep -C 10000"
I've found multiple colors too much work, though, and so just have:
alias highlight="grep --color=always -C 10000"

Comment via: facebook

Recent posts on blogs I like:

Costs are Rising, US Highway Edition

There’s a preliminary paper circulating at Brookings, looking at American infrastructure construction costs. Authors Leah Brooks and Zachary Liscow have tabulated the real costs of the American Interstate program over time, from the 1950s to the 1990s, an…

via Pedestrian Observations July 16, 2019

Nice things

Last night a friend of a friend invited us swimming at a private pond in a Boston exurb. Part of me felt suspicious of the place. Something about the feeling of “this is something rich people do” and the knowledge that the adults chatting in deck chairs w…

via The whole sky July 15, 2019

Deconstruct files

This is a psuedo-transcript for a talk given at Deconstruct 2019. In order to make this accessible for people on slow connections as well as people using screen readers, the slides have been replaced by in-line text (the talk has ~120 slides; at an averag…

via Dan Luu July 12, 2019

more     (via openring)

More Posts:


  ::  Posts  ::  RSS  ::  ◂◂RSS  ::  Contact