How to make the powershell line-buffered in emacs for Windows - powershell

Question

I want to use powershell in emacs, but it seems that the powershell in emacs is block buffered. For example, when I write the a simple c program like this:
int main()
{
printf("input the number of a value: \n");
scanf("%d", &num);
}
I compile it and make it run in Powershell under emacs. It won't print out the line input the number of a value: until I input a number and hit Enter. the c program runs well in powershell outside the emacs. My question is how can I run the PowerShell line buffered in emacs?
edit I use the Powershell.el

Answer 1

The stdout of the C library is line buffered if the stdout of your program is connected to a terminal. The reason you find the behavior in your original program (without fflush) is simply because while running through the GNU EMACS, your program thinks it is not connected to a real terminal. Experiment running your program in M-x term or M-x ansi-term, for example. The solutions given here suggest you using fflush, which is definitely not a solution as you won't change every little program that uses the C library in your system. So the answer to your question is really giving your GNU EMACS a real terminal and not changing your program. Now, the bad news is that neither of these terminals for the GNU EMACS seem to work on Windows. (Sorry.) (Nevertheless, it appears someone claims to run ansi-term on Windows.)

Answer 2

You need to fflush before the fscanf.

Answer 3

This works for me with eshell:
#include <stdio.h>
int main() {
int num;
printf("input the number:\n");
fflush(stdout);
scanf("%d", &num);
printf("inc: %d\n", num + 1);
}
I couldn't reproduce your problem with powershell.el because I see another: it doesn't wait for the input, "reads" a 0 instead, prints "inc: 1" and exits.