$ cp demo_file demo_file1Дemo_file:this line is the 1st lower case line in this file.Дemo_file:Two lines above this line is empty.Дemo_file1:this line is the 1st lower case line in this file.Дemo_file1:Two lines above this line is empty.Дemo_file1:And this is the last line. When the Linux shell sees the meta character, it does the expansion and gives all the files as input to grep. The grep output will also include the file name in front of the line that matched the specific pattern as shown below. For this example, let us copy the demo_file to demo_file1. This is also a basic usage of grep command. Checking for the given string in multiple files. The basic usage of grep command is to search for a specific string in the specified file as shown below.

Search for the given string in a single file This Line Has All Its First Character Of The Word With Upper Case.ДЄnd this is the last line. This line is the 1st lower case line in this file. THIS LINE IS THE 1ST UPPER CASE LINE IN THIS FILE. In this article let us review 15 practical examples of Linux grep command that will be very useful to both newbies and experts.ДЇirst create the following demo_file that will be used in the examples below to demonstrate grep command.

Earlier we discussed 15 practical examples for Linux find command, Linux command line history and mysqladmin command. This is part of the on-going 15 Examples series, where 15 detailed examples will be provided for a specific command or functionality. You should get a grip on the Linux grep command.

Grep in a directory