Instead of writing stuff I decided to chicken out and talk.

Anyways, Windows paths use \ as the path separator. You might see it as horrible (it is), but for globbing it is actually fine since ? and * are disallowed in filenames. You will still need to escape [ and the extglob (, but recall that | is disallowed too so you can just use that as the escape character.

You may or may not need to have a compile step to convert this glob into actual glob(7). For that you just replace all instances of \ with /, and all instances of | with \. The drivename handling will depend on the environment at hand; for Cygwin-based systems, you have:

• (\\\\\?\)^([A-Z]): becomes /proc/cygdrive/$2
• ^\\\\: becomes //

This replacement with cygdrive will inflate the string size and make it impossible to do it in-place, so I recommend not doing it if possible.