How to use the grep command in Linux for searching for, and inside, files

In the vast realm of Linux, an open-source operating system, the grep command holds a significant place. An acronym for ‘Global Regular Expression Print’, the grep command is a widely-used Linux tool that gives users the power to search through text or output based on specific patterns. This command line utility is indispensable for efficient file and data management, serving as a cornerstone in Linux operations.

The grep command’s usefulness is in its versatility and power. Whether you’re debugging a problem by searching through logs, searching through code for a specific function, or even looking for files with a specific keyword, the grep command is an indispensable tool in a Linux user’s toolkit. Its ability to filter output makes it an ideal command for piping with other commands to refine output further.

This very week I used the grep command to search through over 200 desktop files to firstly check they each had a line inside starting with ‘Exec=’ and then I got that line extracted and printed out into an output file that I could examine (instead of opening each every one of the 200+ files).

And liked I used the grep command, it is often used in conjunction with the pipe symbol ‘|’ to further process what grep has extracted, e.g. extract a sub-string or perform some other function.

In fact, the bash shell itself can really do a lot, from prompting for inputs, or reading variables passed to it at runtime, do/while loops, if/then statements, and a lot more. If you want to automate something, you can frequently just use a bash script file in place of a more complex language. But you won’t know unless you just read up a bit on a few of the different commands. If you get stuck, ask Google Bard or similar AI for some help, and it will even spit out some sample code you can use.

See https://www.linuxcapable.com/grep-command-in-linux-with-examples/
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