Mimic Python's strip() function in C

Question

I started on a little toy project in C lately and have been scratching my head over the best way to mimic the strip() functionality that is part of the python string objects

Answer 1

Python strings' strip method removes both trailing and leading whitespace. The two halves of the problem are very different when working on a C "string" (array of char, \0 terminated).

For trailing whitespace: set a pointer (or equivalently index) to the existing trailing \0. Keep decrementing the pointer until it hits against the start-of-string, or any non-white character; set the \0 to right after this terminate-backwards-scan point.

For leading whitespace: set a pointer (or equivalently index) to the start of string; keep incrementing the pointer until it hits a non-white character (possibly the trailing \0); memmove the rest-of-string so that the first non-white goes to the start of string (and similarly for everything following).