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 …
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 …
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 …
grep with logic operators - Unix & Linux Stack Exchange
Jan 5, 2015 · Is there a grep-like utility that will enable me to do grep searches with logic operators. I want to be able to nest and combine the logical constructs freely. For example, stuff like this should be
How can I "grep" for a filename instead of the contents of a file?
grep is used to search within a file to see if any line matches a given regular expression. However, I have this situation - I want to write a regular expression that will match the filename itself (and not the …
How can I use grep to find a word inside a folder?
Nov 8, 2010 · 165 grep -nr string my_directory Additional notes: this satisfies the syntax grep [options] string filename because in Unix-like systems, a directory is a kind of file (there is a term "regular file" …
regex - How can I exclude one word with grep? - Stack Overflow
Dec 27, 2010 · Here grep will try to list all the occurrences of 'wanted_pattern' in all the files from within currently directory and pass it to second grep to filter out the 'unwanted_pattern'. '|' - pipe will tell …
What is the difference between `grep`, `egrep`, and `fgrep`?
Jan 8, 2017 · From "man grep": three variant programs egrep, fgrep and rgrep are available. egrep is the same as grep -E. fgrep is the same as grep -F. rgrep is the same as grep -r. Direct invocation as …