islower -- Lowercase Alphabetic Character Test


SYNOPSIS
#include <ctype.h>
int islower(int c);
DESCRIPTION
islower
tests an integer value c
to determine whether it is a
lowercase alphabetic character.
RETURN VALUE
islower
returns 0 if the character is not a lowercase alphabetic
character, or a nonzero value if it is. If the argument is EOF
, 0
is returned.
CAUTION
The effect of islower
on a noncharacter argument other than
EOF
is undefined. The definition of a lowercase character
is locale dependent. Do not assume that islower
returns either
0 or 1.
EXAMPLE
#include <ctype.h>
#include <stdio.h>
void main()
{
char id[21];
char *text;
int i;
text = "passwordTESTING";
/* Copy uppercase "identifier" from text to id. */
for (i = 0; i < 20 && islower(text[i]); ++i)
id[i] = text[i];
id[i] = '0';
/* Only the word "password" should be copied. */
puts( id);
}
RELATED FUNCTIONS
isalpha
, isupper
, tolower
, toupper
SEE ALSO