Question

我在结构中有一个数组。我正在从一个文件读到一个字符串。我使用strtok获取前几个字符，我想将其余部分传递给结构，最终传递给一个线程。我收到以下错误：

从类型char[1024]

分配类型char *时，

不兼容的类型

参考下面的行和评论。它可能与我如何复制字符数组有关，但我不确定更好的方法。

#include <stdio.h>
#include <pthread.h>
#include <stdlib.h>
#include <linux/input.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

typedef struct 
{
    int period; //stores the total period of the thread
    int priority; // stores the priority
    char pline[1024]; // stores entire line of text to be sorted in function. 
}PeriodicThreadContents;  

int main(int argc, char* argv[])
{
    //opening file, and testing for success
    //file must be in test folder
    FILE *fp;
    fp = fopen("../test/Input.txt", "r");

    if (fp == NULL) 
    {
        fprintf(stderr, "Can't open input file in.list!\n");
        exit(1);
    }

    char line[1024];

    fgets(line, sizeof(line), fp);

    //getting first line of text, containing    
    char *task_count_read = strtok(line," /n");
    char *duration_read = strtok(NULL, " /n");

    //converting char's to integers
    int task_count = atoi(task_count_read);

    int i = 0;

    PeriodicThreadContents  pcontents;




    printf("started threads \n");

    while  (i < task_count)
    {
        fgets(line, sizeof (line), fp);
        strtok(line," ");   

        if (line[0] == 'P')
        {
            char *period_read = strtok(NULL, " ");
            pcontents.period = atoi(period_read);           
            printf("%d",pcontents.period);
            printf("\n");

            char *priority_read = strtok(NULL, " ");
            pcontents.priority = atoi(priority_read);   
            printf("%d",pcontents.priority);
            printf("\n");

            printf("\n%s",line);
            memcpy(&(pcontents.pline[0]),&line,1024);
            printf("%s",pcontents.pline);
        }

    }


    return 0;   
}

Answer 1

C无法像其他语言那样处理字符串。如果不使用辅助功能，C不会进行字符串分配或比较。

要在缓冲区中复制字符串，您可以使用：

strcpy(pcontents.pline, line);

甚至（保证您的字符串不超过1024字节）：

memcpy(pcontents.pline, line, 1024);
pcontents.pline[1023] = '\0';

对于其他字符串操作，请检查：http://www.gnu.org/software/libc/manual/html_node/String-and-Array-Utilities.html#String-and-Array-Utilities

Answer 2

您需要将缓冲区中的字符复制到pcontents.pline中（假设pcontents为PeriodicThreadContents）。

Answer 3

strcpy(pcontents.pline, strtok(NULL, " "));

C中结构的问题

3 个答案: