grep is a Unix command-line utility which searches input passed to it for lines matching a regular expression, and prints the results.

Usage

Use this tag for questions about how to use grep features, how to write regular expressions that work with grep, and general usage. Because grep is now available in Unix-like environments (including Cygwin on Windows), you can also use this tag for compatibility questions, and differences between versions and software environments.

Related tags

• egrep
• zgrep

grep is a Unix command-line utility that searches input passed to it for lines (or NUL-terminated records) matching (or not matching) a regular expression (or regular expressions), and prints the results.  As is typical for Unix command-line utilities, it can take input from files and/or read the standard input.

Usage

Use this tag for questions about how to use grep features, how to write regular expressions that work with grep, and general usage.  Because grep is now available in Unix-like environments (including Cygwin on Windows), you can also use this tag for compatibility questions, and differences between versions and software environments.

Related tags

• egrep
• zgrep
• regex

References

• Man page
• POSIX specification
• GNU grep manual
  Note that the GNU version of grep, which is commonly included with Linux systems, has options / features not specified by POSIX.

grep is a Unix command-line utility which searches input passed to it for lines matching a regular expression, and prints the results.

Usage

Use this tag for questions about how to use grep features, how to write regular expressions that work with grep, and general usage. Because grep is now available in Unix-like environments (including Cygwin on Windows), you can also use this tag for compatibility questions, and differences between versions and software environments.

Related tags

• egrep
• zgrep