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tolower, _tolower, towlower

Convert character to lowercase.

int tolower(
   int c 
);
int _tolower(
   int c 
);
int towlower(
   wint_t c 
);

Parameters

c
Character to convert.

Return Value

Each of these routines converts a copy of c, if possible, and returns the result. There is no return value reserved to indicate an error.

Remarks

Each of these routines converts a given uppercase letter to a lowercase letter if possible and appropriate.

In order for tolower to give the expected results, __isascii and isupper must both return nonzero.

Requirements

Routine Required header Compatibility
tolower <stdlib.h> and <ctype.h> ANSI, Win 98, Win Me, Win NT, Win 2000, Win XP
_tolower <ctype.h> Win 98, Win Me, Win NT, Win 2000, Win XP
towlower <ctype.h> or <wchar.h> ANSI, Win 98, Win Me, Win NT, Win 2000, Win XP

For additional compatibility information, see Compatibility in the Introduction.

Libraries

All versions of the C run-time libraries.

Example

See the example in to Functions.

See Also

Data Conversion Routines | is Routines | to Functions Overview | Run-Time Routines and .NET Framework Equivalents

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