#include <ctype.h>
int islower(int c);
The islower() function tests for any character that is
a lowercase letter or is one of an implementation-defined set of characters
for which none of iscntrl(), isdigit(),
ispunct(), or isspace() is true.
In the C locale, islower()
returns true only for the characters defined as lowercase letters.
The behavior of the islower() function is affected by the
current locale. To modify the behavior, change the LC_CTYPE
category in setlocale(), that is,
setlocale(LC_CTYPE, newlocale). In the C locale or in a locale
where character type information is not defined, characters are classified
according to the rules of the U.S. ASCII 7-bit coded character set.
- c
-
Is an integer whose value is representable as an unsigned char,
or the value of the macro EOF.
The islower() function
returns non-zero for true and zero for false. If the parameter is
not in the domain of the function, the return result is undefined.
ANSI/ISO 9899-1990.
MT-Safe, with exceptions.
This function is MT-Safe as long as no thread calls setlocale() while
this function is executing.
None.
MKS Toolkit for Professional Developers
MKS Toolkit for Enterprise Developers
MKS Toolkit for Enterprise Developers 64-Bit Edition
- Functions:
- isalnum(), isalpha(), isascii(), iscntrl(), isdigit(), isgraph(), isprint(), ispunct(), isspace(), isupper(), isxdigit(), setlocale()
MKS Toolkit 9.3 Documentation Build 6.