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 (-).
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 …
"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 …
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 …
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 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 …
What's the difference between grep -r and -R - Stack Overflow
Mar 31, 2014 · In the man page: -r Read all files under each directory, recursively, following symbolic links only if they are on the command line. what exactly does "being on the command line" means? T...
find difference between two text files with one item per line
Nov 2, 2010 · What better way to find differences than to use a diff tool haha. Is there higher overhead with using this versus grep?
Find all files containing a specific text (string) on Linux
Jun 6, 2013 · How do I find all files containing a specific string of text within their file contents? The following doesn't work. It seems to display every single file in the system. find / -type f -exec grep -H '