tolower, _tolower, towlower, _tolower_l, _towlower_l
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The latest version of this topic can be found at tolower, _tolower, towlower, _tolower_l, _towlower_l.
Converts a character to lowercase.
int tolower( int c ); int _tolower( int c ); int towlower( wint_t c ); int _tolower_l( int c, _locale_t locale ); int _towlower_l( wint_t c, _locale_t locale );
Parameters
[in] c
Character to convert.
[in] locale
Locale to use for locale-specific translation.
Each of these routines converts a copy of c to lower case if the conversion is possible, and returns the result. There is no return value reserved to indicate an error.
Each of these routines converts a given uppercase letter to a lowercase letter if it is possible and relevant. The case conversion of towlower is locale-specific. Only the characters relevant to the current locale are changed in case. The functions without the _l suffix use the currently set locale. The versions of these functions that have the _l suffix take the locale as a parameter and use that instead of the currently set locale. For more information, see Locale.
In order for _tolower to give the expected results, __isascii and isupper must both return nonzero.
Generic-Text Routine Mappings
| TCHAR.H routine | _UNICODE & _MBCS not defined | _MBCS defined | _UNICODE defined |
|---|---|---|---|
_totlower | tolower | _mbctolower | towlower |
_totlower_l | _tolower_l | _mbctolower_l | _towlower_l |
|
| Routine | Required header |
|---|---|
tolower | <ctype.h> |
_tolower | <ctype.h> |
towlower | <ctype.h> or <wchar.h> |
For additional compatibility information, see Compatibility in the Introduction.
See the example in to Functions.
Data Conversion
is, isw Routines
to Functions
Locale
Interpretation of Multibyte-Character Sequences