Converts a character to lowercase.
#include <ctype.h> int tolower (int character);
If the argument represents an uppercase letter, and there is a corresponding lowercase letter, as defined by character type information in the program locale category LC_TYPE, the corresponding lowercase letter is returned.
If the argument is not an uppercase character, it is returned unchanged.
x | The lowercase letter corresponding to the argument. Or, the unchanged argument, if it is not an uppercase character. |