Use command grep and locate

Question

How I can make the grep command locate certain words in the files specified by the routes found by the locate command?

locate my.cnf | grep user

(I want that grep command search the word "user" on the files found for locate command)

score 17 · Answer 1 · answered Sep 10 '12 at 15:46

17

Try:

locate my.cnf | xargs grep user

answered Sep 10 '12 at 15:46

cha0site

This option is correct, but Matt responded first and it works. Thanks. – Jhonathan Sep 10 '12 at 16:07
3

@Jhonathan - if the result is fairly small, matt's works. If the result can be arbitrarily large, you should prefer `xargs`. – Robᵩ Sep 10 '12 at 19:19
For options necessary for spaces in file paths, see answer of Marko Kudjerski below. – Markus Jun 17 '23 at 14:50

score 16 · Accepted Answer · answered Sep 10 '12 at 15:48

16

Instead of a pipe, use command replacement:

grep user `locate my.cnf`

answered Sep 10 '12 at 15:48

matt b

1

I like this one better than the `xargs` approach below because it maintains grep's highlighting – Michael Osl Jun 09 '14 at 14:04
1

@moeso: You can get grep to always give color output with `--color=always`. – cha0site Mar 29 '15 at 10:47

score 2 · Answer 3 · answered Sep 10 '12 at 15:54

2

In order to play nice with situations when locate results have spaces in names, you could do this

locate -0 my.cnf | xargs -n1 -0 grep user

answered Sep 10 '12 at 15:54

Marko Kudjerski

Shows the same output three times – Jhonathan Sep 10 '12 at 16:04
Without any switches `grep` automatically outputs all of the matching lines (your file likely has multiple lines that match). If you wish to show line numbers in front of them you could use `-n` switch for grep. Otherwise, you could have it output only the first match for every file with `-m 1` or only the name of the file that matches with `-l`. – Marko Kudjerski Sep 11 '12 at 14:55
`locate -0` is indeed necessary if file paths contain spaces. However, in bash, to see the full path of the file, I have to add `-H` to grep, like so: `locate -0 *.tex | xargs -n1 -0 grep -H user` – Markus Jun 17 '23 at 14:52

score 0 · Answer 4 · answered Sep 10 '12 at 15:44

0

Probably grep user $(locate my.cnf) is what you're looking for, if I understand your question correctly.

answered Sep 10 '12 at 15:44

lanzz

4

Note that this will crash and burn if that `locate` command returns too much data. Command line size is not infinite. – cha0site Sep 10 '12 at 15:47

4 Answers4