Grep display both matched and umatched lines

Question

How can I use grep command to display both matched and unmatched lines? Matched line should be in red and other lines should be in normal color.

Is there a grep option available to do that?

try `man grep`, the answer is hard to miss even if you put in minimal effort — Anthon, Jul 23 '14 at 11:01
Please do not cross post: http://stackoverflow.com/questions/24907702/grep-display-both-matched-and-unmatched — fedorqui, Jul 24 '14 at 14:52

Stéphane Chazelas · Accepted Answer · 2014-07-23T12:05:30.883

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grep --color=always -e pattern -e '$'

edited Jul 23 '14 at 12:05

answered Jul 23 '14 at 10:26

Stéphane Chazelas

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@Stéphane Chazelas: This does not work for me, matched pattern is not colored. Any suggestion? My `$TERM` is `vt100`. – cuonglm Jul 23 '14 at 10:38
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@Gnouc, the vt100 terminal is monochrome. The first DEC terminal to support colors [was VT241](http://www.vt100.net/vt_history). But I doubt you're using a real VT100 terminal. In any case GNU `grep` doesn't use `$TERM`, it hardcodes the ANSI escape sequences (regardless of whether your terminal supports (or claims to support) them or not). If `grep 'x\|$'` works, so should `grep -e X -e '^'` though. Also, check your environment for `GREP_COLOR` or `GREP_COLORS` variables. – Stéphane Chazelas Jul 23 '14 at 10:50
@StéphaneChazelas: Suprising, `grep 'x\|$'` works but `grep -e X -e '^'`, `GREP_COLOR` and `GREP_COLORS` both are null. I'm on Windows machine, using `Secure Shell client` to connect to my Linux Server. – cuonglm Jul 23 '14 at 10:54
@StéphaneChazelas: Oh, after testing, I see that `grep -e X -e '^'` works but `grep -e '^' -e X` like your answer does not. – cuonglm Jul 23 '14 at 10:55
@Gnouc, which version of grep is that? I've updated the answer. – Stéphane Chazelas Jul 23 '14 at 11:42
`grep (GNU grep) 2.5.1` – cuonglm Jul 23 '14 at 11:46
@Gnouc, interestingly `grep --color -e x -e '^'` segfaults in OS/X (FreeBSD grep 2.5.1) but not with `$`, so I've updated the answer once again for better portability. – Stéphane Chazelas Jul 23 '14 at 12:09
@StéphaneChazelas: Do you have any ideal why `grep --color -e x -e '^'` cause a segfaults? – cuonglm Jul 24 '14 at 15:22

score 1 · Answer 2 · answered Jul 23 '14 at 10:33

1

Try this:

grep --color=always -e 'pattern\|$' file

answered Jul 23 '14 at 10:33

cuonglm

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score 0 · Answer 3 · answered Jul 23 '14 at 11:17

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If you want to match other lines to have some context, you can use the -A and -B options:

grep --color=always -A 9 -B 9 -e pattern

will give you 9 lines of context. If this is not sufficient, you can increase this value.

answered Jul 23 '14 at 11:17

vinc17

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Grep display both matched and umatched lines

3 Answers3