产生一个软中断 geninterrupt

[c]代码库

#include <conio.h> 
#include <dos.h> 

/* function prototype */ 
void writechar(char ch); 

int main(void) 
{ 
   clrscr(); 
   gotoxy(80,25); 
   writechar('*'); 
   getch(); 
   return 0; 
} 

/* 
   outputs a character at the current cursor 
   position using the video BIOS to avoid the 
   scrolling of the screen when writing to 
   location (80,25). 
*/ 

void writechar(char ch) 
{ 
   struct text_info ti; 
   /* grab current text settings */ 
   gettextinfo(&ti); 
   /* interrupt 0x10 sub-function 9 */ 
   _AH = 9; 
   /* character to be output */ 
   _AL = ch; 
   _BH = 0;                  /* video page */ 
   _BL = ti.attribute;  /* video attribute */ 
   _CX = 1;           /* repetition factor */ 
   geninterrupt(0x10);  /* output the char */ 
}