islower() function in C

Using the islower() function in C

The islower() function in C is used to check whether a character is lowercase. The function takes a character as input and returns a non-zero value if the character is lowercase, or zero if the character is not lowercase.

Here is an example of how to use the islower() function:

#include <stdio.h>
#include <stdint.h>
#include <ctype.h>

int32_t main(int32_t argc, char const *argv[])
{
    char c = 'a';

    int32_t result = islower(c);

    if (result > 0x00)
    {
        printf("The character '%c' is a lowercase.\n", c);
    }
    else
    {
        printf("The character '%c' is not a lowercase.\n", c);
    }

    return 0;
}

The islower() function takes a character as input and returns a non-zero value if the character is lowercase, or zero if the character is not lowercase. In this example, the character 'a' is lowercase, so the function will return a non-zero value and the printf() statement will print the output.

Explore the complete list of functions available in ctype header in C standard library.

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Written by

Muhammad Hassaan Shah
Muhammad Hassaan Shah

Passionate about new technological trends and like to share practical tips and tutorials about C, C++, Python, MATLAB, STM32, Arduino, ESP32, and more …