al_ustr_offset - Man Page

#include <allegro5/allegro.h>

int al_ustr_offset(const ALLEGRO_USTR *us, int index)

Return the byte offset (from the start of the string) of the code point at the specified index in the string. A zero index parameter will return the first character of the string. If index is negative, it counts backward from the end of the string, so an index of -1 will return an offset to the last code point.

If the index is past the end of the string, returns the offset of the end of the string.

al_ustr_length(3)

al_ref_ustr(3), al_ustr_assign_substr(3), al_ustr_dup_substr(3), al_ustr_insert(3), al_ustr_length(3), al_ustr_remove_chr(3), al_ustr_replace_range(3).