// Tutorial //

Using the getch() function in C/C++

Published on August 3, 2022
Default avatar

By Vijaykrishna Ram

Using the getch() function in C/C++

While we believe that this content benefits our community, we have not yet thoroughly reviewed it. If you have any suggestions for improvements, please let us know by clicking the “report an issue“ button at the bottom of the tutorial.

In this article, we’ll take a look at using the getch() function in C/C++.

The getch() function is very useful if you want to read a character input from the keyboard.

While this is not a part of the C standard, this is still a POSIX C function. So, we can still use this function from Windows / Linux / Mac.

Let’s take a look at using this function, using a few examples.


Basic Syntax of getch() in C/C++

This function takes in a single character from the standard input (stdin), and returns an integer.

This is there as part of the <conio.h> header file, so you must include it in your program.

#include <conio.h>
int getch();

This function does not take any parameters.

Here, getch() returns the ASCII value of the character read from stdin.

For example, if we give the character ‘0’ as input, it will return the ASCII value of ‘0’, which is 49.

Now, in C / C++, we can directly convert a character to an integer. So on typecasting, the ASCII value 49 will be cast to the char value of ‘0’!

Let’s now look at some examples.


Using getch() in C/C++ - Some Examples

As a simple example, let’s first look at reading a single character.

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

int main() {
    char ch = getch();
    printf("Received Input: %c\n", ch);
    return 0;
}

Sample Output

Received Input: a

I got this output, after I typed ‘a’ on my keyboard. Let’s now look at a program, which waits for 5 characters from the keyboard.

Note that getch() will NOT display the input from the keyboard. So, when you type the input, the cursor won’t show the input.

Let’s display the complete string only after we get all 5 characters

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

int main() {
    // Set op = {0, 0, 0, 0, 0, 0} = '\0\0\0\0\0\0' string
    char op[6] = {0};
    for (int i=0; i<5; i++) {
        op[i] = getch();
    }
    printf("Received 5 character Input: %s\n", op);
    return 0;
}

Output

Received 5 character Input: Hello

Indeed, when I typed “Hello”, I did get the output correctly.

Notice that I have 6 characters in my output string, since we need to reserve 1 byte for ‘\0’. So op is “Hello\0”.


Conclusion

In this article, we learned about using the getch() function in C / C++ to receive character input from the keyboard.

For more content on C and C++, do go through our tutorial section on C programming!

References


Thanks for learning with the DigitalOcean Community. Check out our offerings for compute, storage, networking, and managed databases.

Learn more about us


Want to learn more? Join the DigitalOcean Community!

Join our DigitalOcean community of over a million developers for free! Get help and share knowledge in our Questions & Answers section, find tutorials and tools that will help you grow as a developer and scale your project or business, and subscribe to topics of interest.

Sign up now
About the authors
Default avatar
Vijaykrishna Ram

author

Still looking for an answer?

Ask a questionSearch for more help

Was this helpful?
 
JournalDev
DigitalOcean Employee
DigitalOcean Employee badge
January 7, 2021

This is not entirely correct, both getch() (and _getch() since getch() has been deprecated) can actually return 2 integers. You said: “This function takes in a single character from the standard input (stdin), and returns an integer.” For instance arrow keys return 2 integers…

- Luis Escajeda

    Try DigitalOcean for free

    Click here to sign up and get $200 of credit to try our products over 60 days!
    Try DigitalOcean for free