int al_ustr_offset(const ALLEGRO_USTR *us, int index)
Introduced in 5.0.0

Return the offset (in bytes 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.

See also: al_ustr_length

Examples: ex_blend, ex_ttf, ex_utf8

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