PCRE: ^|$ and \A|\Z?

Question

In PCRE, what's the difference between:

• ^ and \\A , and
• $ and \\Z ?

I remember reading there was a subtle difference, but can't recall exactly what it was.

Answer 1

By default, there is no difference between the two, they both signify the start or end of the string. If, however, you use the m modifier, then ^ and $ will match the start and end of lines, respectively.