int tolower ( int c ); |
<cctype> |
Convert uppercase letter to lowercase
Converts parameter c to its lowercase equivalent if c is an uppercase letter and has a lowercase equivalent. If no such conversion is possible, the value returned is c unchanged.
Notice that what is considered a letter may depend on the locale being used; In the default C locale, an uppercase letter is any of: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z, which translate respectivelly to: a b c d e f g h i j k l m n o p q r s t u v w x y z.
Parameters
- c
- Uppercase letter character to be converted, casted to an int, or EOF.
Return Value
The lowercase equivalent to
c, if such value exists, or
c (unchanged) otherwise. The value is returned as an
int value that can be implicitly casted to
char.
Example
/* tolower example */
#include <stdio.h>
#include <ctype.h>
int main ()
{
int i=0;
char str[]="Test String.\n";
char c;
while (str[i])
{
c=str[i];
putchar (tolower(c));
i++;
}
return 0;
} |
Output:
See also
| toupper | Convert lowercase letter to uppercase (function) |
| isupper | Check if character is uppercase letter (function) |
| islower | Check if character is lowercase letter (function) |
| isalpha | Check if character is alphabetic (function) |