Input && Output, Part2.

What does getchar() do?

The getchar() function gets a character from the standard input. It does not have arguments hence, the parentheses are always empty.

It is defined this way:

#include <stdio.h>

int getchar();

Technically, getchar() is not a function. It is a macro. A macro is a shortcut based on another function, as defined in the <stdio.h> header file. This is why the <stdio.h> header file is to be included within your source code.

The real function to get characters from standard input is getc(); and it is defined in this way:

#include <stdio.h>

int c;

c = getc(stdin);

In the above example, getc(); reads from the stdin as defined in the header file. The function returns an integer value, which is stored in variable c.

NB: getchar(); returns an integer value and not a character value.

Sample Code:

#include <stdio.h>

int main(void)
{
int i;

printf(" The character is: ");
i=getchar();
printf("%c. \n", i);
return(0);
}

When the getchar() function is invoked, the character returned is stored in the i integer variable. The second printf() function will display the character stored in the variable. It is important to note that the %c placeholder is used to display single characters. This is because the integer variable, i, contains a character value.

How To Create a Program That Displays a Character’s ASCII Code Value In Decimal.

When the %d placeholder is used instead of %c, whatever will be displayed when the code is run is the variable's ASCII code value. This is because %d displays that value instead of a character value. To understand this, you have to consider that a computing device will treat all information as ones and zeros under the hood and the ASCII code is a value of the information that will be presented to you. It is only when information is displayed as a character, %c, does it look like text. This is how I created an ASCII-Program