While loop asking for input until ctrl-d using C

Question

I want to make a while loop that is continually asking a user for input until the user ctrl-d\'s out of it. How can I do this correctly? I am using this ri

Answer 1

You have to test for EOF, which is what CTRL-D returns.

So do this:

while ( fgets( ... ) != NULL ) {
    ...
}

EDIT:

Since you're prompting, even better would be:

for ( ;; ) {
    printf( "enter input: " );
    fflush( NULL );   // make sure prompt is actually displayed, credit Basile Starynkevitch
    if ( fgets( input, ... ) == NULL ) break;

    // handle input here
}

Answer 2

A ctrl-d will send an EOF (end of file) character, which translates in fgets as a NULL pointer :

while (fgets(user_input, 1000, stdin) != NULL) {
    // do stuff...
}
// no more user input