$re = '/#Command handler
#===============
#Start of the line
^ #Match the command name
(?<cmd>[\w\d\-\_\?]+)
#Catch as many parameters as possible
(?<params>
(
\ +
(?<pre>[^\-\\\\\/\w\d\s\n\r]?)
[^\"]*\k<pre>
)*
)?
#Catch as many switches as possible and save them into group
(?<switches>
(
\ +
#Switch starts with -- or - or /
(?:\-\-|\-|\/)
#Gotcha!
[\w\d\_]+
)*
)?
#At the end of the line can be some spaces
\ *$ #End of the line/mx';
$str = 'help
echo "lol"
shutdown -s /f';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php