C String – strlwr() function

strlwr() function in C String converts all the characters present in a given string to Lowercase.

The strlwr() function is defined in the header file string.h.

It takes a single argument that is the name of the string and is written as follows.

strlwr(string_name);

C Program for strlwr() function

#include <stdio.h>
#include <string.h>

int main() 
{
  char str[20] = "SIMple2CODe.CoM";
  
  printf("Original String: %s", str);  
  printf("Lowercasing all the Characters: %s", strlwr(str));  
 
  return 0;
}

Output:

Don’t be alarmed if it does not run on your compiler. It is just that some functions like strlwr(), which are only available in ANSI C (Turbo C/C++) and are not available in the standard C-GCC compiler.