linux - What is the point of "grep -q" - Stack Overflow
May 16, 2019 · Moreover, this is a lot faster than a regular grep invocation, since it can exit immediately when the first match is found, rather than needing to unconditionally read (and write) to the end of file.
How do I recursively grep all directories and subdirectories?
Feb 16, 2016 · If you find yourself frequently using grep to do recursive searches (especially if you manually do a lot of file/directory exlusions), you may find ack (a very programmer-friendly grep …
What is the difference between grep -e and grep -E option?
grep -e PATTERN unless, as stated in an earlier Answer and in the man pages, there are multiple search patterns, or to protect a pattern beginning with a hyphen (-).
regex - Using the star sign in grep - Stack Overflow
Jul 6, 2016 · grep * means "0 or more", and grep is greedy by default. Note that in grep basic regular expressions the metacharacters ?, + , { , | , ( , and ) lose their special meaning.
How can I grep the results of FIND using -EXEC and still output to a ...
Dec 17, 2014 · To expand on @gilles answer to make it a little more informative, especially if the list of files you're dealing with is large, you can report the file name (relative path) of each file along with the …
"grep -rnw": search for a string in all files - Stack Overflow
grep -rnw '/path/to/somewhere/' -e "pattern" However lately I encountered a problem, shown in the following picture: Looks like this command only recognizes strings that stand out as a word or …
How to run grep with multiple AND patterns? - Unix & Linux Stack …
Mar 25, 2016 · I would like to get the multi pattern match with implicit AND between patterns, i.e. equivalent to running several greps in a sequence: grep pattern1 | grep pattern2 | ... So how to …
UNIX grep command (grep -v grep) - Stack Overflow
Apr 5, 2015 · 11 grep when used with ps -ef also outputs the grep used for filtering the output of ps -ef. grep -v grep means that do not include the grep used for filtering in the command output. You can …
How to perform grep operation on all files in a directory?
435 Working with xenserver, and I want to perform a command on each file that is in a directory, grep ping some stuff out of the output of the command and appending it in a file. I'm clear on the …
How to make multi-line regexp work in grep? - Stack Overflow
May 8, 2025 · However when I try to use it with grep, it does not work. I tried with -e, -P and -E. The errors I get: invalid option -- ' ' or no match at all. Any online regexp verification tool will tell you what …