hmm
I got it. It's a command-line setup Asci or UTF-8. Noting to do with c compiler.
Output is like this
Code:#include <stdio.h> int main () { printf("\x81 \x94 \x99 \x9A\n"); printf("ü ö Ö Ü\n"); printf("\x2e\n"); return 0; }Thank you all.Code:� � � � ü ö Ö Ü .