I'm trying to wite some extension in C.
It's is intended for reading/writing id3 tags from MP3 files.
But problem has raised while developing.

How can i return (for ex) Cyrillic string to TCL interpreter to be shown OK.
In C code I have char* filled with my Cyrillic words.

But when i set result of command with 

Tcl_SetObjResult(interp, Tcl_NewStringObj(buf, -1));

unknown symbols are shown instead of correct word.