在Eclipse中运行时，不会出现C ++程序的输入提示

Question

I am beginning desktop programming with c++, and when I run the following code:

   #include <stdio.h>
    int main (int argc, char ** argv){
    enum{ max_string = 127};
    static char string[max_string + 1] = "";

    printf("Type in a line\n");
    fgets(string,max_string,stdin);
    printf("the string is %s\n",string);
    return 0;
}

I don't see the "Type in a line" prompt when I run the program inside Eclipse. Instead if I just type in a response, I see what I typed followed by:

Type in a line
the string is Hello World

Why doesn't it first show the prompt "type in a line" before I type in my input?

Answer 1

You need to flush the output buffer. I just added std::cout << std::endl; and include <iostream> . I would suggest you start using std::cout instead of printf . It's type safe. I tested this inside of Eclipse, without the flush, the line doesn't show up, with the flush it does.

If you don't want to move to <iostream> I just tested fflush(stdout) from <stdio.h> and it works too. However, I strongly encourage the move, stdio.h is the standard for C, the iostream is the standard for C++ and since you're learning C++...