Synopsis:
    #include <ctype.h>
    int tolower( int c );
    int _tolower( int c );
    #include <wchar.h>
    wint_t towlower( wint_t c );

Description:
    The tolower function converts c to a lowercase letter if c represents an
    uppercase letter.

    The _tolower function is a version of tolower to be used only when c is
    known to be uppercase.

    The towlower function is similar to tolower except that it accepts a
    wide-character argument.

Returns:
    The tolower function returns the corresponding lowercase letter when the
    argument is an uppercase letter; otherwise, the original character is
    returned.  The towlower function returns the corresponding
    wide-character lowercase letter when the argument is a wide-character
    uppercase letter; otherwise, the original wide character is returned.

    The result of _tolower is undefined if c is not an uppercase letter.

Example:
    #include <stdio.h>
    #include <ctype.h>

    char chars[] = {
        'A',
        '5',
        '$',
        'Z'
    };

    #define SIZE sizeof( chars ) / sizeof( char )

    void main()
      {
        int   i;

        for( i = 0; i < SIZE; i++ ) {
            printf( "%c ", tolower( chars[ i ] ) );
        }
        printf( "\n" );
      }

    produces the following:

    a 5 $ z

Classification:
    tolower is ANSI, _tolower is not ANSI, towlower is ANSI

Systems:
     tolower - All, Netware

    _tolower - All, Netware
    towlower - All, Netware

See Also:
    isalnum, isalpha, iscntrl, isdigit, isgraph, islower, isprint, ispunct,
    isspace, isupper, iswctype, isxdigit, strlwr, strupr, toupper