Question

创建了一个结构，如下所示：

struct entry
{
    int source[5];
    int destination[5];
    int type[5];
    int port;
    int data;
} record;

用户必须输入文件名，文件需要根据特定条件进行验证然后存储，但我不知道如何在我的代码中使用malloc或calloc函数来允许我这样做。还需要有关如何验证文本文件的帮助。代码片段如下所示：

int file()
{   
    FILE *inFile;
    char inFileName[70]= {'\0'};
    char data1[70];
    char *token;

    int x = 0;
    int count = 0;
    int length = 0;

    printf("Enter File Name:");
    scanf("%s", inFileName);

    if ((inFile = fopen(inFileName, "r"))== NULL)
    {
        printf("Open failed:%s\n", inFileName);
        exit(1);
    }

    if (inFile != NULL)
    {
        while (!feof (inFile)) // Read the whole file until the end of the file.
        {
            count ++;
            printf("\n\nRecord:%i\n", count);
            fgets(data1, sizeof data1, inFile); //fgets reads the first string from the "inFile"        pointer and stores it in char "data" using the "sizeof" function to make sure strings are the same size.

            token = strtok(data1, ":"); // the "token" pointer used with the "strtok" function to break down the "data" string into smaller tokens by using the delimiter ":"
            record.source[5] = token;
            printf("Source:%d\n", record.source);

Answer 1

您可以使用它来获取文件大小：

How do you determine the size of a file in C?

然后做一个这样大小的malloc。

off_t size = fsize(inFileName);
char *data = malloc((size + 1) * sizeof(char));
off_t offset = 0;

并在fgets存储数据之后：

fgets(data1, sizeof data1, inFile);
strcpy(data + offset, data1);
offset += strlen(data1);

需要使用malloc或calloc为要存储的文本文件中的数据分配内存以及如何验证文件中的数据

1 个答案: