What flavour of regular expression is grep?

Question

I\'m guessing it\'s not a Perl Compatible Regular Expression, since there\'s a special kind of grep which is specifically PCRE. What\'s grep most simil

Answer 1

There is no regular grep function in PHP. If you are referring to the ereg family of PHP functions then those are POSIX regular expressions. If you are referring to the Linux grep commandline utility, those are POSIX regular expressions as well. It supports both basic as well as extended POSIX regular expressions.