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 (-).
How do I recursively grep all directories and subdirectories?
Feb 16, 2016 · grep -r "texthere" . The first parameter represents the regular expression to search for, while the second one represents the directory that should be searched. In this case, . means the …
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.
Using the star sign in grep - Stack Overflow
Jul 6, 2016 · grep itself doesn't support wildcards on most platforms. You have to use egrep to use wildcards. Shells have a different syntax. "*" in the shell is <any string>. In egrep it's an operator that …
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...
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 …
How to perform grep operation on all files in a directory?
430 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 …
Negative matching using grep (match lines that do not contain foo ...
How do I match all lines not matching a particular pattern using grep? I tried this: grep '[^foo]'
bash - How to grep, excluding some patterns? - Stack Overflow
I'd like find lines in files with an occurrence of some pattern and an absence of some other pattern. For example, I need find all files/lines including loom except ones with gloom. So, I can find ...
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 '