Thread: A Few Short Questions....

Using your old code, you would not actually have to enter the number twice. You could enter it once, and then press Return twice. What happens, is that you tell you program to input that variable, and then a new-line character. When it inputs the variable, it makes the user press enter before moving on. So it's almost as if it had to wait for 2 new line characters.

On my system you Actually still have to enter the number twice.

as to the OP. you need to put extra getchar because of the way scanf works. This function takes a string - that is a sequence of chars - and formats it according to your conversion specifier. It stops on the first whitespace, and assigns the sequence to the address of the argument in this case - in.
In the case of the second code

Code:

#include <stdio.h>
int main(void)
{
    int in;
    
    printf("Please enter an ascii number to convert: ");
    scanf("%d", &in);
    printf("You entered %d, the regular value is %c\n", in, in);
    getchar();
    getchar();
    return 0;
}

Once you've entered your input, your press enter to flush your input to stdout - your monitor - the '\n' is stored in stdin as part of your input and scanf reads that as part of your string and acts on it. subsequently you get a '\n' in your code, which satifies the getchar() function, which reads the next chr from stdin. which leads to program termination.
So if you code getchar() twice, the first accepts the '\n' in the printf statement, the second waits for your input and then terminates.
the general rule of thumb is not to use scanf, but instead fgets. Which i'm sure you'll come to soon.

Originally Posted by tyouk

actually a quicker method is to include conio.h into your program and then just use the _getch() which only requires input of one character

Regards,
Tyouk

the conio.h is not portable. If your learning ANSI C learn ANSI C. why complicate it.