如何在C ++中读取system（）调用的结果？

Z时代
2024-01-10
分类：问答

我正在使用以下代码来尝试使用读取dfLinux中命令的结果popen。

#include <iostream> // file and std I/O functions
int main(int argc, char** argv) {
    FILE* fp;
    char * buffer;
    long bufSize;
    size_t ret_code;
    fp = popen("df", "r");
    if(fp == NULL) { // head off errors reading the results
        std::cerr << "Could not execute command: df" << std::endl;
        exit(1);
    }
    // get the size of the results
    fseek(fp, 0, SEEK_END);
    bufSize = ftell(fp);
    rewind(fp);
    // allocate the memory to contain the results
    buffer = (char*)malloc( sizeof(char) * bufSize );
    if(buffer == NULL) {
        std::cerr << "Memory error." << std::endl;
        exit(2);
    }
    // read the results into the buffer
    ret_code = fread(buffer, 1, sizeof(buffer), fp);
    if(ret_code != bufSize) {
        std::cerr << "Error reading output." << std::endl;
        exit(3);
    }
    // print the results
    std::cout << buffer << std::endl;
    // clean up
    pclose(fp);
    free(buffer);
    return (EXIT_SUCCESS);
}