功 能


用 法

int signal(int sig, sigfun fname);


/* This example installs a signal handler routine for SIGFPE, 
   catches an integer overflow condition, makes an adjustment 
   to AX register, and returns. This example program MAY cause 
   your computer to crash, and will produce runtime errors 
   depending on which memory model is used. 

#pragma inline 
#include <stdio.h> 
#include <signal.h> 

void Catcher(int sig, int type, int *reglist) 
   printf("Caught it!n"); 
   *(reglist + 8) = 3;             /* make return AX = 3 */ 

int main(void) 
   signal(SIGFPE, Catcher); 
   asm     mov     ax,07FFFH       /* AX = 32767 */ 
   asm     inc     ax              /* cause overflow */ 
   asm     into                    /* activate handler */ 

   /* The handler set AX to 3 on return. If that hadn't happened, 
      there would have been another exception when the next 'into' 
      was executed after the 'dec' instruction. */ 
   asm     dec     ax              /* no overflow now */ 
   asm     into                    /* doesn't activate */ 
   return 0;