al_ustr_insert
bool al_ustr_insert(ALLEGRO_USTR *us1, int pos, const ALLEGRO_USTR *us2)
Insert us2 into us1 beginning at pos. pos cannot be less than 0. If pos is past the end of us1 then the space between the end of the string and pos will be padded with NUL ('\0') bytes. pos is specified in bytes.
Use al_ustr_offset to find the byte offset for a code-points offset
Returns true on success, false on error.
See also: al_ustr_insert_cstr, al_ustr_insert_chr, al_ustr_append
Examples: ex_utf8
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