iswlower

C

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Technical Specifications

Strings library

Byte strings

Multibyte strings

Wide strings

Null-terminated wide strings

Functions
Character manipulation
iswalnum (C95) iswalpha (C95) iswlower (C95) iswupper (C95) iswdigit (C95) iswxdigit (C95) iswblank (C99) wctype (C95) iswctype (C95)	iswcntrl (C95) iswgraph (C95) iswspace (C95) iswprint (C95) iswpunct (C95) towlower (C95) towupper (C95) wctrans (C95) towctrans (C95)
Conversions to numeric formats
wcstolwcstoll (C95)(C99) wcstoulwcstoull (C95)(C99)	wcstofwcstodwcstold (C99)(C95)(C99) wcstoimaxwcstoumax (C99)(C99)
String manipulation
wcslenwcsnlen_s (C95)(C11) wcscpywcscpy_s (C95)(C11) wcsncpywcsncpy_s (C95)(C11) wcscatwcscat_s (C95)(C11) wcsncatwcsncat_s (C95)(C11) wcsstr (C95)	wcscmp (C95) wcsncmp (C95) wcscoll (C95) wcsxfrm (C95) wcschr (C95) wcsrchr (C95) wcspbrk (C95) wcsspn (C95) wcscspn (C95) wcstokwcstok_s (C95)(C11)
Array manipulation
wmemcpywmemcpy_s (C95)(C11) wmemmovewmemmove_s (C95)(C11)	wmemcmp (C95) wmemchr (C95) wmemset (C95)

Defined in header <wctype.h>
int iswlower( wint_t ch );		(since C95)

Checks if the given wide character is a lowercase letter, i.e. one of abcdefghijklmnopqrstuvwxyz or any lowercase letter specific to the current locale.

Parameters

ch

-

wide character

Return value

Non-zero value if the wide character is an lowercase letter, zero otherwise.

Notes

ISO 30112 specifies which Unicode characters are include in POSIX lower category.

Example

Run this code

#include <stdio.h>
#include <wchar.h>
#include <wctype.h>
#include <locale.h>

int main(void)
{
    wchar_t c = L'\u0444'; // Cyrillic small letter ef ('Æ')
    printf("in the default locale, iswlower(%#x) =%d\n", c, !!iswlower(c));
    setlocale(LC_ALL, "en_US.utf8");
    printf("in Unicode locale, iswlower(%#x) =%d\n", c, !!iswlower(c));
}

Output:

in the default locale, iswlower(0x444) = 0
in Unicode locale, iswlower(0x444) = 1

References

• C11 standard (ISO/IEC 9899:2011):

• 7.30.2.1.7 The iswlower function (p: 450)

• C99 standard (ISO/IEC 9899:1999):

• 7.25.2.1.7 The iswlower function (p: 396)

See also

islower

checks if a character is lowercase (function)

ASCII values			characters	iscntrl iswcntrl	isprint iswprint	isspace iswspace	isblank iswblank	isgraph iswgraph	ispunct iswpunct	isalnum iswalnum	isalpha iswalpha	isupper iswupper	islower iswlower	isdigit iswdigit	isxdigit iswxdigit
decimal	hexadecimal	octal
08	\x0\x8	\0\10	control codes (NUL, etc.)	0	0	0	0	0	0	0	0	0	0	0	0
9	\x9	\11	tab (\t)	0	0	0	0	0	0	0	0	0	0	0	0
1013	\xA\xD	\12\15	whitespaces (\n, \v, \f, \r)	0	0	0	0	0	0	0	0	0	0	0	0
1431	\xE\x1F	\16\37	control codes	0	0	0	0	0	0	0	0	0	0	0	0
32	\x20	\40	space	0	0	0	0	0	0	0	0	0	0	0	0
3347	\x21\x2F	\41\57	!"#$%&'()*+,-./	0	0	0	0	0	0	0	0	0	0	0	0
4857	\x30\x39	\60\71	0123456789	0	0	0	0	0	0	0	0	0	0	0	0
5864	\x3A\x40	\72\100	:;<=>?@	0	0	0	0	0	0	0	0	0	0	0	0
6570	\x41\x46	\101\106	ABCDEF	0	0	0	0	0	0	0	0	0	0	0	0
7190	\x47\x5A	\107\132	GHIJKLMNOP QRSTUVWXYZ	0	0	0	0	0	0	0	0	0	0	0	0
9196	\x5B\x60	\133\140	[\]^_`	0	0	0	0	0	0	0	0	0	0	0	0
97102	\x61\x66	\141\146	abcdef	0	0	0	0	0	0	0	0	0	0	0	0
103122	\x67\x7A	\147\172	ghijklmnop qrstuvwxyz	0	0	0	0	0	0	0	0	0	0	0	0
123126	\x7B\x7E	\172\176	{|}~	0	0	0	0	0	0	0	0	0	0	0	0
127	\x7F	\177	backspace character (DEL)	0	0	0	0	0	0	0	0	0	0	0	0