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 …
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 …
find difference between two text files with one item per line
Nov 2, 2010 · grep -Fxvf file1 file2 What the flags mean: -F, --fixed-strings Interpret PATTERN as a list of fixed strings, separated by newlines, any of which is to be matched. -x, --line-regexp …
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 …
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 …
grepping using the result of previous grep - Stack Overflow
Sep 20, 2015 · Is there a way to perform a grep based on the results of a previous grep, rather than just piping multiple greps into each other. For example, say I have the log file output …
How do I fetch lines before/after the grep result in bash?
Sep 16, 2012 · The second grep command. "grep -oP", finds the matching string and prints everything after it until it reaches the end of the current line, while excluding the matching string.
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 …
What's the difference between "grep -e" and "grep -E"
Jun 16, 2013 · So I wonder what's the difference between these 2 options. According to man grep: -E, --extended-regexp Interpret pattern as an extended regular expression (i.e. force grep 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 …