没遇到过的C错误

Question

shell_command(char gcommand[100]) {
    FILE *pipe = popen("ls", "r");
    char output[100];

    if ( pipe ) {
        fgets(output, sizeof output, pipe);
        pclose(pipe);
    }
    return output;
}

结果

program.c: In function ‘shell_command’:
program.c:42: warning: return makes integer from pointer without a cast
program.c:42: warning: function returns address of local variable

我用谷歌搜索了两天没有成功

Answer 1

您已将函数声明为

shell_command(char gcommand[100])

被编译器解释为

int shell_command(char gcommand[100])

如你所愿

char* shell_command(char gcommand[100])

这是行不通的，因为输出是一个堆栈变量并返回未定义的行为，正如您的编译器告诉您的那样。