View source for Global Regular Expression Print

= grep =

Print lines from text that match patterns, basic regex is used by default</br>

== Use ==
<code>grep /etc/ssh/sshd_config pattern</code> match pattern in /etc/sshd_config, case sensitive</br>
</br>
3 characters before and 4 characters after</br>
<code>echo "some123_string_and_another" | grep -o -P '.{0,3}string.{0,4}'</code></br>
result: 23_string_and</br>

== Useful Flags ==
<code>-E</code> use extended regex</br>
<code>-A x</code> print x lines after matched pattern</br>
<code>-B x</code> print x lines before matched pattern</br>
<code>-C x</code> print x lines before and after matched pattern, results separated by "--"</br>
<code>-c</code> print number of matches</br>
<code>-i</code> case insensitive</br>
<code>-mX</code> limit number of matches to X</br>
<code>-n</code> print line number from file</br>
<code>-o</code> only print matched pattern</br>
<code>-R</code> recursive search in a given folder, follow symlinks</br>
<code>-r</code> recursive search in a given folder, don't follow symlinks</br>
<code>-v</code> match inverse</br>
<code>-w</code> match whole words only</br>