为 Linux 创建 C 程序时出现浮点异常（核心转储）

Question

I am new to C and need some help, when I execute this code, the output shows "Floating point exception (core dumped)" instead of a number which I don't know what it could be. I don't really know what is wrong with my code since I am a total beginner with Linux and C. Every help is appreciated.

Here is my functions.c:

#include "header.h"

int count(FILE *file){
    int count=0,n; 
    char word[WORDS];
    while(fscanf(file,"%s",word)==1 ){ 
        count++;
    };
    return count;
};

int total(FILE *file){ 
    int numbers, sum=0;
    int token;
    while(token!=EOF){ 
        token=fscanf(file,"%d",&numbers);
        sum+=numbers;
    };
    return sum;
};

and here is my main.c:

#include "header.h"

int main(){
    char word[WORDS];
    char theFile[WORDS]; 
    FILE *fileptr;
    printf("Enter the file name: ");
    scanf("%s",theFile); 

    printf("Reading file %s...\n", theFile);
    fileptr=fopen(theFile,"r");

    if(fileptr==NULL){ 
        fprintf(stderr,"ERROR: The file '%s' does not exist\n", theFile);
        return 1;
    };

    int theSum=total(fileptr); 
    int theCount=count(fileptr); 
    int theMean= theSum/theCount; 

    printf("Average weight: %d \n", theMean);

    return 0;
};

Answer 1

In this statement

int theMean= theSum/theCount;

when theCount is 0 you are dividing by zero, which is undefined behavior and is probably causing the FPE.

Answer 2

The main reason for getting Floating point exception is that you are accessing the file beyond its size.

In function total and count you are using the same pointer, so when done with total the file pointer is at the end of file, and you are using the same in count also.

you need to do fseek(file,SEEK_SET,0); , to make the pointer point at the beginning.

and all of you block statements and functions are end by ; , thats wrong.

I have corrected the program as a whole assuming that the contents of the file are just numbers like this 1 2 3 4 5 6

#include <stdio.h>

#define WORDS 100

int count(FILE *file){
    int count = 0,n; 
    char word[WORDS];
    // you need this to access the elements from start of the file
    // comment below line causes sigfpe, Floating point exception
    fseek(file,SEEK_SET,0);
    printf(" position of fptr in count = %d\n",ftell(file));
    while(fscanf(file,"%s",word)==1 ){ 
        count++;
    }
    return count;
}

int total( FILE *file ){ 
    int numbers, sum = 0;
    int token;
    // This is checked after number is read, will add the last number 2 times 
    //while(token != EOF){ 
    while(1)
    {
        token = fscanf(file,"%d",&numbers);
        printf("N = %d, token = %d\n", numbers, token);
        if(token == EOF )
            break;
        sum += numbers;
    }
    printf(" position of fptr in total  at the end = %d, sum = %d\n",ftell(file), sum);
    return sum;
}

int main(){
    char word[WORDS];
    char theFile[WORDS]; 
    FILE *fileptr;
    printf("Enter the file name: ");
    scanf("%s",theFile); 

    printf("Reading file %s...\n", theFile);
    fileptr=fopen(theFile,"r");

    if(fileptr == NULL){ 
        fprintf(stderr,"ERROR: The file '%s' does not exist\n", theFile);
        return 1;
    }

    int theSum = total(fileptr); 
    int theCount = count(fileptr); 
    //make sure to add a check that `theCount` is not zero
    int theMean = theSum/theCount; 

    printf("Average weight: %d \n", theMean);

    return 0;
}