Question

我执行了一个命令“watch grep \”cpu MHz \“/ proc / cpuinfo”。执行此命令后，我得到了以下结果。 Result of The Command

但是当我使用c代码尝试此命令时。

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

int main(){
    FILE *fp;
    char path[1035];
    char command[]="watch grep \"cpu MHz \" /proc/cpuinfo";
    fp = popen(command, "r");
    if (fp == NULL) {
            printf("Failed to run command\n" );
        exit(1);
    }

    /* Read the output a line at a time - output it. */
    while (fgets(path, sizeof(path)-1, fp) != NULL) {
        printf("%s",path);
    }
    pclose(fp);
    return 0;
}
    I am getting following result.

Result of The Code 告诉我哪里出错了？

Answer 1

尝试这样的事情：

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

int main(void){
    FILE *fp;
    char path[1035];
    char command[]="while grep \"cpu MHz\" /proc/cpuinfo; do sleep 2; done";
    fp = popen(command, "r");
    if (fp == NULL) {
            printf("Failed to run command\n" );
        exit(1);
    }

    /* Read the output a line at a time - output it. */
    while (fgets(path, sizeof(path), fp) != NULL) {
        printf("%s",path);
    }
    pclose(fp);
    return 0;
}

Answer 2

我认为这就是你想要的。不要忘记使用memset。

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

int main()
{
    FILE *fp;
    char path[1035];
    char command[]="watch grep 'cpu MHz'  /proc/cpuinfo";

    fp = popen(command, "r");
    if (fp == NULL) {
        printf("Failed to run command\n" );
        exit(1);
    }

    memset(path,'\0',sizeof(path));
    /* Read the output a line at a time - output it. */
    while (fgets(path, sizeof(path)-1, fp) != NULL) {
        printf("%s",path);
    }
    pclose(fp);
    return 0;
}

如何使用c代码将linux命令的结果复制到字符串中？

2 个答案: