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In the examples below, we will use grep instead of extended grep. We stored the file in the directory of the test user, that is, in /home/test/sample.txt How to Grep Multiple Patterns in a File In our case, we named the file sample.txt and added a few paragraphs of text. To make sure you understand how to use grep to search multiple strings, we suggest creating a file with some text on which we are going to try out a couple of different use cases.

Examples of Using Grep for Multiple Strings, Patterns and Words The pipe character | is also treated as a meta character in extended grep. These characters are the parenthesis (), curly brackets, and question mark.

The difference between grep and extended grep is that extended grep includes meta characters that were added later. The egrep command is an outdated version of extended grep. To do so, use the -e flag and keep adding the desired number of search patterns: grep -e pattern1 -e pattern2 fileName_or_filePath What is the Difference Between grep, grep -E, and egrep? egrep 'pattern1|pattern2' fileName_or_filePathĪnother option is to add multiple separate patterns to the grep command. The deprecated version of extended grep is egrep. grep -E 'pattern1|pattern2' fileName_or_filePath This option treats the pattern you used as an extended regular expression. The latest way to use grep is with the -Eoption. grep 'pattern1\|pattern2' fileName_or_filePath Use the backslash before pipe | for regular expressions. The patterns need to be enclosed using single quotes and separated by the pipe symbol. The basic grep syntax when searching multiple patterns in a file includes using the grep command followed by strings and the name of the file or its path. A user with permissions to access the necessary files and directories.