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In this tutorial, we are going to discuss some unformatted input functions in C which are used to read the input entered by the user, when using the keyboard at the console. These input values could be of any primitive data type or an array type. Some of the most important unformatted console input functions are -

Unformatted Console Input Functions	Description
getch()	Reads a single character entered by the user at the console, without echoing it.
getche()	Reads a single character entered by the user at the console, and echoing it.
getchar()	Reads a single character entered by the user at the console, and echoing it, but needs the Enter key to be pressed by the user at the end.
gets()	Reads a single string entered by the user at the console.








Why the functions are called unformatted console input functions?


While calling any of the unformatted console input functions, we do not have to use any format specifiers in them, to read a value from console. Hence, these functions are named unformatted console input functions.






• Example of getch(), getche(), getchar() function


Now we are going to explain how to use getche(), getche and getchar() function in a coding example.



/* C - Example of getch(), getche(), getchar() */


#include<stdio.h>
#include<conio.h>

int main()
{
	int ch;

	printf("Running getch(), please enter a character : ");

	/* getch() does not echo the pressed character key on the screen */
	ch = getch();

	printf("\n");
	printf("The character value you have just entered : %c", ch);
	printf("\n");



	printf("Running getche(), please enter a character : ");

	/*getche() function does echo the pressed character key on the screen */
	ch = getche();

	printf("\n");
	printf("The character value you have just entered : %c", ch);
	printf("\n");


	printf("Running getchar(), please enter a character : ");

	/*getchar() function echoes the pressed character key and also requires the ENTER key at the end */
	ch = getchar();
	printf("The character value you have just entered : %c", ch);

	return 0;
}




Output




Running getch(), enter a character :
The character value you have just entered : a
Running getche(), enter a character : g
The character value you have just entered : g
Running a getchar(), enter a character : w
The character value you have just entered : w




Program Analysis



• On pressing the character key 'a', the getch() stores the character in ch, but does not echo it on the screen.
• On pressing the character key 'g', the getche() stores the character in ch, and echoes it on the screen.
• On pressing the character key 'w', the getchar() echoes it on the screen, but waits for the Enter key to be pressed to store the character in ch variable.





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• Using gets() function to read a string


We can read a string entered by the user by using an in-built unformatted console I/O function, gets(). Let's see how it done.



/* C - Using gets() function to read a string */ 


#include<stdio.h>

int main()
{
	char country[20];
	printf("Enter a country you want to visit : ");
	gets(country);
	printf("The country you want to visit is :  %s", country);

	return 0;
}




Output




Enter a country you want to visit : United Kingdom
The country you want to visit is :  United Kingdom




Program Analysis


As you can see in the example, the whole multi-word string i.e. name of the country entered by the user gets stored in the char array by using the in-built gets() function, which we couldn't have achieved by using the scanf() function. And unlike scanf() method, the gets() method does not take any format specifier as a parameter but only takes the name of char array.

This concludes our tutorial on unformatted input functions in C. In the next tutorial, we are going to explain some unformatted output functions with their coding examples, so please, stay tuned!






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