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__asm__(".code16gcc\n");
void vga_graphics_write_at_offset(char, short);
void vga_graphics_write(char);
void vga_graphics_write_str(char*);
static short CURSOR_LOC = 0;
void _start() {
vga_graphics_write('a');
vga_graphics_write('/');
vga_graphics_write('b');
char foo[] = "hello how are you";
vga_graphics_write_str(foo);
while(1) { }
}
void vga_graphics_write_str(char* str) {
while(*str) {
vga_graphics_write(*str++);
}
}
void vga_graphics_write(char value) {
vga_graphics_write_at_offset(value, CURSOR_LOC);
CURSOR_LOC += 2;
}
void vga_graphics_write_at_offset(char value, short offset) {
__asm__(
"mov %0, %%al \n"
"mov %1, %%di \n"
"mov %%al, %%gs:(%%di) \n"
: :"r"(value), "r"(offset) : "%ax", "%di");
}
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