C语言程序运行报错Process returned -1073741819 (0xC0000005)求助

DevOps 小满

2026-7-24

程序运行崩溃（错误码0xC0000005）的问题排查与修复

我写了一段C语言代码完成练习，编译没有警告和错误，但运行时直接崩溃，报错Process returned -1073741819 (0xC0000005)。我自己找了很久没找到原因，作为编程新手，求各位给点建议。

users.csv文件格式要求：<身份证号>;<观影数量>;<年龄>;<职业>，示例数据如下：

1234;18;10;student
3253;22;3;sommelier
1;16;100;teacher
1743;50;5;retired
9654;28;18;student

我的代码

/*
Write a program that takes in input a file with data relative to users from
a streaming site, loads them in memory in a structured type variable and, 
after having sorted them by age in ascending order, writes in a new file
the data relative to only the users that are students.
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

const int MAX = 100;                // I wasn't able to use a preprocessor command (such as '#define MAX 100') | error: expected identifier or '(' before numeric constant | so I declared a constant global variable

typedef struct {
    int id, age, watched_movies;
    char occupation[30];
} USER[100];                        // can't initialize with MAX ( ==> cannot initialize arrays with variable sized elements)

//Written 'MAX' as 'max' to avoid variable shadowing and confusion in function building
void sort_users(USER* U, int max);
void print_students(USER* U, int max);

int main(void)
{
    FILE* usersPtr;

    if ((usersPtr = fopen("users.csv", "r")) == NULL) {
        puts("File 'users.csv' could not be opened.");
        exit(1);
    } else {
        USER U[100] = {{{0, 0, 0, ""}}};    // added braces to remove compiler warning
        for (int i = 0; i < MAX; ++i) {
            U[i]->id = 99999;
            U[i]->age = 0;
            U[i]->watched_movies = 0;
            strcpy(U[i]->occupation, "");
        }

        int i = 0;
        char string[60] = {""};
        char* strPtr;
        while (!feof(usersPtr)) {
            fscanf(usersPtr, "%s", string);

            strPtr = strtok(string, ";");
            U[i]->id = atoi(strPtr);

            strPtr = strtok(NULL, ";");
            U[i]->age = atoi(strPtr);

            strPtr = strtok(NULL, ";");
            U[i]->watched_movies = atoi(strPtr);

            strPtr = strtok(NULL, ";");
            strcpy(U[i]->occupation, strPtr);

            i++;
        }
        strPtr = NULL;

        sort_users(U, MAX);
        print_students(U, MAX);

        printf("%s", "The 'students.csv' file has been created and filled with the relevant pieces of information.\n");

        fclose(usersPtr);
        usersPtr = NULL;
    }
    return 0;
}

void sort_users(USER* U, int max)       // ("bubble sorting")
{
    for (int i = 0; i < max; ++i) {
        for (int j = max - 1; j != i; --j) {

            if (U[j]->age <= U[i]->age) {
                USER T[1] = {{{0, 0, 0, ""}}};                  // create a temporary array of structs (of 1 element)

                T[0]->id = U[i]->id;
                T[0]->age = U[i]->age;
                T[0]->watched_movies = U[i]->watched_movies;
                strcpy(T[0]->occupation, U[i]->occupation);

                T[i]->id = U[j]->id;
                T[i]->age = U[j]->age;
                T[i]->watched_movies = U[j]->watched_movies;
                strcpy(T[i]->occupation, U[j]->occupation);

                T[j]->id = U[0]->id;
                T[j]->age = U[0]->age;
                T[j]->watched_movies = U[0]->watched_movies;
                strcpy(T[j]->occupation, U[0]->occupation);
            }
        }
    }
}

void print_students(USER* U, int max)
{
    FILE* studentsPtr;

    if ((studentsPtr = fopen("students.csv", "w")) == NULL) {
        puts("File 'students.csv' could not be created.");
        exit(1);
    } else {
        for (int i = 0; i < max; ++i) {
            if (strcmp(U[i]->occupation, "student") == 0) {
                fprintf(studentsPtr, "%d,%d,%d,%s\n", U[i]->id, U[i]->age, U[i]->watched_movies, U[i]->occupation);
            }
        }
        fclose(studentsPtr);
        studentsPtr = NULL;
    }
}

问题排查与修复建议

结构体定义完全错误：你把USER定义成了包含100个结构体的数组类型，导致后续所有U[i]->的写法都是在错误地操作指针，直接触发内存越界。正确的做法是先定义单个用户结构体，再声明数组：
```
typedef struct {
    int id, age, watched_movies;
    char occupation[30];
} User;
#define MAX 100
User U[MAX];
```
访问成员时用.而不是->，比如U[i].id。
MAX宏定义问题：之前用#define MAX 100报错，肯定是你加了分号或者语法错误。宏定义不需要分号，正确写法就是#define MAX 100，用宏定义比全局const更适合指定数组大小。
feof循环逻辑错误：while (!feof(usersPtr))会导致最后一次循环重复读取（因为feof是读取失败后才置位），还可能让i超过MAX导致数组越界。改成读取成功才进入循环：
```
int i = 0;
char string[60];
while (i < MAX && fscanf(usersPtr, "%s", string) == 1) {
    // 解析逻辑
    i++;
}
```
排序函数逻辑混乱且越界：sort_users里的临时数组T只有1个元素，但你却访问T[i]、T[j]，直接越界写内存，这是崩溃的直接原因之一。冒泡排序的正确逻辑是交换相邻元素，用单个临时结构体即可：
```
void sort_users(User* U, int count)
{
    for (int i = 0; i < count - 1; ++i) {
        for (int j = 0; j < count - i - 1; ++j) {
            if (U[j].age > U[j+1].age) {
                User temp = U[j];
                U[j] = U[j+1];
                U[j+1] = temp;
            }
        }
    }
}
```
注意这里传入的应该是实际读取的用户数量i，而不是MAX，避免处理未初始化的空数据。
初始化冗余：原来的USER U[100] = {{{0, 0, 0, ""}}};写法复杂，改成User U[MAX] = {0};就能完成所有成员的初始化，不需要额外循环赋值。

修复后的完整代码

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define MAX 100

typedef struct {
    int id, age, watched_movies;
    char occupation[30];
} User;

void sort_users(User* U, int count);
void print_students(User* U, int count);

int main(void)
{
    FILE* usersPtr = fopen("users.csv", "r");
    if (!usersPtr) {
        puts("File 'users.csv' could not be opened.");
        exit(1);
    }

    User U[MAX] = {0};
    int i = 0;
    char string[60];
    char* strPtr;

    while (i < MAX && fscanf(usersPtr, "%s", string) == 1) {
        strPtr = strtok(string, ";");
        if (strPtr) U[i].id = atoi(strPtr);

        strPtr = strtok(NULL, ";");
        if (strPtr) U[i].age = atoi(strPtr);

        strPtr = strtok(NULL, ";");
        if (strPtr) U[i].watched_movies = atoi(strPtr);

        strPtr = strtok(NULL, ";");
        if (strPtr) strncpy(U[i].occupation, strPtr, sizeof(U[i].occupation)-1);
        // 用strncpy避免缓冲区溢出

        i++;
    }

    sort_users(U, i);
    print_students(U, i);

    puts("The 'students.csv' file has been created and filled with the relevant pieces of information.");

    fclose(usersPtr);
    return 0;
}

void sort_users(User* U, int count)
{
    for (int i = 0; i < count - 1; ++i) {
        for (int j = 0; j < count - i - 1; ++j) {
            if (U[j].age > U[j+1].age) {
                User temp = U[j];
                U[j] = U[j+1];
                U[j+1] = temp;
            }
        }
    }
}

void print_students(User* U, int count)
{
    FILE* studentsPtr = fopen("students.csv", "w");
    if (!studentsPtr) {
        puts("File 'students.csv' could not be created.");
        exit(1);
    }

    for (int i = 0; i < count; ++i) {
        if (strcmp(U[i].occupation, "student") == 0) {
            fprintf(studentsPtr, "%d;%d;%d;%s\n", U[i].id, U[i].watched_movies, U[i].age, U[i].occupation);
            // 输出格式和输入一致用分号，或者按需求改逗号
        }
    }

    fclose(studentsPtr);
}

内容的提问来源于stack exchange，提问作者Gisvaldo

C语言程序运行报错Process returned -1073741819 (0xC0000005)求助

我的代码 #

问题排查与修复建议 #

修复后的完整代码 #

我的代码

问题排查与修复建议

修复后的完整代码