tolower, _mbctolower, towlower

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Header File

ctype.h, mbstring.h

Category

Conversion Routines

Prototype

int tolower(int ch);

int towlower(wint_t ch); // Unicode version

unsigned int _mbctolower(unsigned int c);

Description

Translates characters to lowercase.

tolower is a function that converts an integer ch (in the range EOF to 255) to its lowercase value (a to z; if it was uppercase, A to Z). All others are left unchanged.

Return Value

tolower returns the converted value of ch if it is uppercase; it returns all others unchanged.

Example

#include <string.h>
#include <stdio.h>
#include <ctype.h>
int main(void)
{
   int length, i;
   char *string = "THIS IS A STRING";
   length = strlen(string);
   for (i=0; i<length; i++)
   {
       string[i] = tolower(string[i]);
   }
   printf("%s\n",string);
   return 0;
}

Portability

	POSIX	Win32	ANSI C	ANSI C++
tolower	+	+	+	+
_mbctolower		+
towlower		+	+	+