Thread: getchar () and declare variable

Your intuition is right. A while loop sounds perfect. if you have an ascii based system (as most do), then all your letters and numbers you input, are already in ascii value. Whether an 'a' is printed as an 'a', or as it's ascii value of 64, depends on how you ask for it to be printed:

1) as a letter: a

or

2) as a number: 97

Here's a small start to your program.

Code:

printf("\n Enter q to quit ");
while((ch=getchar()) != 'q') 
   printf("\n %c equals %d ", ch, ch);

If you don't have a quick reference for the ascii table values, goto:
ascii tables
and download one. You'll use it a lot while you're programming.

Why does the above code work on so many keypresses at once? Because your system has a keyboard buffer that will hold - better yet, you tell me how many keypresses the keyboard buffer on your system will hold.


And welcome to the forum.

this is exactly what I needed ! Thanks !

and I guess the keyboard buffer could hold infinite keypress isn't it?

by the way what's the purpose for the 2nd ch in the statement

printf("\n %c equals %d ", ch, ch);

this is the first time I see such coding^^"

Hi i have another question,
I wanna carry out a bit rotation (shift right to 1bits for 1st ASCII value, shift right 2bits for 2nd value and so on, until the 8th value with no bit rotation), how could this be done combine with the getchar() ?

I am thinking of turn the ACSII into binary number , and then do the bit rotation,

yet I google out and found that there shd be an easier way to directly carry out bit rotation with ACSII value,
but I am uncertain how to form the coding.