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[lhb_780902]

下面是我在MSDN中看到的一段代码，是介绍longjmp的用法的，但在我的机器上编译过不去。
#include "stdafx.h"
#include <stdio.h>
#include <signal.h>
#include <setjmp.h>
#include <stdlib.h>
#include <float.h>
#include <math.h>
#include <string.h>

jmp_buf mark;
int fperr;

void __cdecl fphandler(int sig, int num);
void fpcheck(void);

typedef void (__cdecl * PFUNC)(int);

void main(void)
{
double n1, n2, r;
int jmpret;
PFUNC pFunc = fphandler;

_control87(0, _MCW_EM);

if (signal(SIGFPE, pFunc) == SIG_ERR){
fprintf(stderr, "Couldn't set SIGFPE\n");
abort();
}

jmpret = setjmp(mark);
if (jmpret == 0){
printf("Test for invalid operation - ");
printf("enter two numbers: ");
scanf("%lf %lf", &n1, &n2);

r = n1 / n2;
printf("\n\n%4.3g / %4.3g = %4.3g\n", n1, n2, r);

r = n1 * n2;
printf("\n\n%4.3g * %4.3g = %4.3g\n", n1, n2, r);
} else{
fpcheck();
}
}

void __cdecl fphandler(int sig, int num)
{
fperr = num;

_fpreset();

longjmp(mark, -1);
}

void fpcheck(void)
{
char fpstr[30];

switch(fperr){
case _FPE_INVALID:
strcpy(fpstr, "Invalid number");
break;
case _FPE_OVERFLOW:
strcpy(fpstr, "Overflow");
break;
case _FPE_UNDERFLOW:
strcpy(fpstr, "Underflow");
break;
case _FPE_ZERODIVIDE:
strcpy(fpstr, "Divide by zero");
break;
default:
strcpy(fpstr, "Other floating point error");
break;
}

printf("Error %d: %s\n", fperr, fpstr);
}

[zqone]

错误信息

[zhenxizhou]

显示了什么错误，请提供。

[KcSoft]

up

[jishiping]

错误和longjmp的用法无关。而是函数不匹配的错误。
将 fphandler(int sig, int num) 改成 fphandler(int num) 就可以了（共2处）。

[jishiping]

上面已经说了，是函数参数个数不匹配的问题。写全了就是：
include "stdafx.h"
#include <stdio.h>
#include <signal.h>
#include <setjmp.h>
#include <stdlib.h>
#include <float.h>
#include <math.h>
#include <string.h>

jmp_buf mark;
int fperr;

void __cdecl fphandler(int num);
void fpcheck(void);

typedef void (__cdecl * PFUNC)(int);

void main(void)
{
double n1, n2, r;
int jmpret;
PFUNC pFunc = fphandler;

_control87(0, _MCW_EM);

if (signal(SIGFPE, pFunc) == SIG_ERR){ //就是这里，signal的回调函数的参数错误。
fprintf(stderr, "Couldn't set SIGFPE\n");
abort();
}

jmpret = setjmp(mark);
if (jmpret == 0){
printf("Test for invalid operation - ");
printf("enter two numbers: ");
scanf("%lf %lf", &n1, &n2);

r = n1 / n2;
printf("\n\n%4.3g / %4.3g = %4.3g\n", n1, n2, r);

r = n1 * n2;
printf("\n\n%4.3g * %4.3g = %4.3g\n", n1, n2, r);
} else{
fpcheck();
}
}

void __cdecl fphandler(int num)
{
fperr = num;

_fpreset();

longjmp(mark, -1);
}

void fpcheck(void)
{
char fpstr[30];

switch(fperr){
case _FPE_INVALID:
strcpy(fpstr, "Invalid number");
break;
case _FPE_OVERFLOW:
strcpy(fpstr, "Overflow");
break;
case _FPE_UNDERFLOW:
strcpy(fpstr, "Underflow");
break;
case _FPE_ZERODIVIDE:
strcpy(fpstr, "Divide by zero");
break;
default:
strcpy(fpstr, "Other floating point error");
break;
}

printf("Error %d: %s\n", fperr, fpstr);
}

[bllb007]

学习!

[lhb_780902]

你可以看一下MSDN中关于setjmp的例子就知道我说的问题了

[lhb_780902]

原文是这样的
include "stdafx.h"
#include <stdio.h>
#include <signal.h>
#include <setjmp.h>
#include <stdlib.h>
#include <float.h>
#include <math.h>
#include <string.h>

jmp_buf mark;
int fperr;

void __cdecl fphandler(int sig, int num);
void fpcheck(void);

typedef void (__cdecl * PFUNC)(int, int); //错误处在这

void main(void)
{
double n1, n2, r;
int jmpret;
PFUNC pFunc = fphandler;

_control87(0, _MCW_EM);

if (signal(SIGFPE, pFunc) == SIG_ERR){ //就是这里，signal的回调函数的参数错误。
fprintf(stderr, "Couldn't set SIGFPE\n");
abort();
}

jmpret = setjmp(mark);
if (jmpret == 0){
printf("Test for invalid operation - ");
printf("enter two numbers: ");
scanf("%lf %lf", &n1, &n2);

r = n1 / n2;
printf("\n\n%4.3g / %4.3g = %4.3g\n", n1, n2, r);

r = n1 * n2;
printf("\n\n%4.3g * %4.3g = %4.3g\n", n1, n2, r);
} else{
fpcheck();
}
}

void __cdecl fphandler(int sig, int num)
{
fperr = num;

_fpreset();

longjmp(mark, -1);
}

void fpcheck(void)
{
char fpstr[30];

switch(fperr){
case _FPE_INVALID:
strcpy(fpstr, "Invalid number");
break;
case _FPE_OVERFLOW:
strcpy(fpstr, "Overflow");
break;
case _FPE_UNDERFLOW:
strcpy(fpstr, "Underflow");
break;
case _FPE_ZERODIVIDE:
strcpy(fpstr, "Divide by zero");
break;
default:
strcpy(fpstr, "Other floating point error");
break;
}

printf("Error %d: %s\n", fperr, fpstr);
}