Question

...目前正在练习填充包含数组的结构（用于存储多个元素的char数组）。我想尝试实施的方案如下：

一般任务是（存储学生信息，姓名作为字符串，学生作为一个列表或char **）
学生信息首先从文件中加载！（myfile.txt）
标记化/解析学生信息并加载到struct

包含我的学生信息的文件是：

myfile.txt （每行包含学生姓名和课程列表）由＆＃34;分隔：＆＃34;

.testi

我的main.c是：

background-color: rgba(0, 0, 0, 0.8);

面临的问题是填补＆＃34; Austin Barbra:Biology,chemistry,maths,music Romio Chandra:Mechanics,IT,Geology,music,Astronomy . .＆＃34;结构的成员。我从内部for循环获取seg_fault（在j上迭代）。我错过了我的代码吗？

Answer 1

我快速修复它以使它不会崩溃并且输出正确，它可能更好（我们可以修复泄漏）但它实际上现在打印你的东西。

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

#define path "myfile.txt"

typedef struct student_info {
    char *studt_name;
    char *cources_as_string;
    char **cources_as_list;
} std_info;

std_info *myinfo; //a global var that will conatain student info
int student_count = 0, cource_count = 0;

void load_file() {
    int i, yu, index = 0;
    char *line = NULL, *token = NULL;
    size_t len = 0;
    FILE *fp;
    fp = fopen(path, "r");
    if (fp == NULL) {
        perror("FILE OPEN ERROR[IN load_file]: ");
        return;
    }
    if ((myinfo = (struct student_info *) malloc(2 * sizeof(*myinfo))) == NULL)//malloc for 2 students
        puts("malloc fail");
    while (getline(&line, &len, fp) != -1) {
        strtok(line, "\n");
        char *token;

        token = strtok(line, ":");
        myinfo[index].studt_name = malloc(200 * sizeof(char));
        strcpy(myinfo[index].studt_name, token);

        token = strtok(NULL, ":");
        myinfo[index].cources_as_string = malloc(200 * sizeof(char));
        strcpy(myinfo[index].cources_as_string, token);
        index++;
    }
    student_count = index;
    //fclose(fp);
}

char **return_cource_list(char *cources_string) {
    char *token;
    char **cource_list = malloc(sizeof(char *) * 10);
    int index = 0;
    //course_string is delimited by ",": (eg. Biology,chemistry,maths,music). parse this and add to my char ** variable.
    token = strtok(cources_string, ",");
    cource_list[0] = token;
    while (token != NULL) {
        cource_list[index] = strdup(token);
        token = strtok(NULL, ",");
        index++;
    }
    cource_count = index;
    return cource_list;

}

/* returns an array of char*, all of which NULL */
char **alloc_argv(unsigned rows) {
    char **matrix = malloc(rows * sizeof(char *));
    if (!matrix) abort();

    for (unsigned row = 0; row < rows; row++) {
        matrix[row] = malloc(rows * sizeof(char *));
        matrix[row] = "\0";
        if (!matrix[row]) abort();

    }
    return matrix;
}

int main() {
    int i, j;
    load_file();
    for (i = 0; i < student_count; i++) {
        printf("============================\n");
        printf("NAME: %s >>COURCE_string: %s\n", myinfo[i].studt_name, myinfo[i].cources_as_string);
        char ip_list[200];
        char **std_cource_list = return_cource_list(myinfo[i].cources_as_string);
        for (j = 0; j < cource_count; j++) {
            printf("\tCOURCE_list[%d]: %s\n", j, std_cource_list[j]);
            //segmentation fault exists here, to copy "std_cource_list[j]" to my struct...(need help here).


            myinfo[i].cources_as_list = alloc_argv(100);
            myinfo[i].cources_as_list[j] = malloc(sizeof(char **));
            strcpy(myinfo[i].cources_as_list[j], std_cource_list[j]);
        }
    }
}

输出

============================
NAME: Austin Barbra >>COURCE_string: Biology,chemistry,maths,music
    COURCE_list[0]: Biology
    COURCE_list[1]: chemistry
    COURCE_list[2]: maths
    COURCE_list[3]: music
============================
NAME: Romio Chandra >>COURCE_string: Mechanics,IT,Geology,music,Astronomy
    COURCE_list[0]: Mechanics
    COURCE_list[1]: IT
    COURCE_list[2]: Geology
    COURCE_list[3]: music
    COURCE_list[4]: Astronomy

Process finished with exit code 0

将包含char **数组的结构填充为成员C

1 个答案: