harderr，是建立一个硬件错误处理程序，程序例是trap disk errors and prompt。
函数名: harderr
功 能: 建立一个硬件错误处理程序
用 法: void harderr(int (*fptr)());
程序例:
/*This program will trap disk errors and prompt
the user for action. Try running it with no
disk in drive A: to invoke its functions.*/
#include
#include
#include
#define IGNORE 0
#define RETRY 1
#define ABORT 2
int buf[500];
/*define the error messages for trapping disk problems*/
static char *err_msg[] = {
};
error_win(char *msg)
{
int retval;
cputs(msg);
/*prompt for user to press a key to abort, retry, ignore*/
while(1)
{
retval= getch();
if (retval == 'a' || retval == 'A')
{
retval = ABORT;
break;
}
if (retval == 'r' || retval == 'R')
{
retval = RETRY;
break;
}
if (retval == 'i' || retval == 'I')
{
retval = IGNORE;
break;
}
}
return(retval);
}
/*pragma warn -par reduces warnings which occur
due to the non use of the parameters errval,
bp and si to the handler.*/
#pragma warn -par
int handler(int errval,int ax,int bp,int si)
{
static char msg[80];
unsigned di;
int drive;
int errorno;
di= _DI;
/*if this is not a disk error then it was
another device having trouble*/
if (ax < 0)
{
/* report the error */
/* and return to the program directly requesting abort */
hardretn(ABORT);
}
/* otherwise it was a disk error */
drive = ax & 0x00FF;
errorno = di & 0x00FF;
/* report which error it was */
err_msg[errorno], 'A' + drive);
/*
return to the program via dos interrupt 0x23 with abort, retry,
or ignore as input by the user.
*/
hardresume(error_win(msg));
return ABORT;
}
#pragma warn +par
int main(void)
{
/*
install our handler on the hardware problem interrupt
*/
harderr(handler);
clrscr();
getch();
return 0;
}