In GNU grep, there is no difference in available functionality between basic and extended syntaxes. In other implementations, basic regular expressions are less powerful.

In the synopsis's first form, which is used if no -e or -f options are present, the first operand PATTERNS is one or more patterns separated by newline characters, and grep prints each line that matches a …

-E, --extended-regexp: Interpret PATTERNS as extended regular expressions (EREs). -F, --fixed-strings: Interpret PATTERNS as fixed strings, not regular expressions.

Nov 3, 2025 · The grep command is one of the most useful tools in Linux and Unix systems. It is used to search for specific words, phrases, or patterns inside text files, and shows the matching lines on your …

Aug 2, 2007 · The grep utilities are a family that includes grep, grep -E (formally egrep), and grep -F (formally fgrep) for searching files. For most use cases, fgrep is sufficient due to speed and only …

Nov 14, 2025 · The grep -e command in Linux is a powerful tool for searching multiple patterns in text files. By understanding its fundamental concepts, usage methods, common practices, and best …

In this tutorial, we explored the common syntax of the grep command followed by various options that can be used with it. Additionally, several practical examples were provided to illustrate its usefulness.

Sep 10, 2023 · The Linux grep command is a string and pattern matching utility that displays matching lines from multiple files. It also works with piped output from other commands.

In addition, two variant programs egrep and fgrep are available. egrep is the same as grep -E. fgrep is the same as grep -F. Direct invocation as either egrep or fgrep is deprecated, but is provided to allow …

Jan 1, 2024 · grep -e command allows you to use multiple patterns at once. -e option indicates an expression in the grep command. Suppose, you need to search three different patterns in a file then …