al_ref_buffer
ALLEGRO_USTR *al_ref_buffer(ALLEGRO_USTR_INFO *info, const char *s, size_t size)
Like al_ref_cstr but the size of the string data is passed in as a parameter. Hence you can use it to reference only part of a string or an arbitrary region of memory.
The string is valid while the underlying C string is valid.
See also: al_ref_cstr, al_ref_ustr
Examples: ex_utf8
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