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_lrotl, _lrotr

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Rotate bits to the left (_lrotl) or right (_lrotr).

unsignedlong_lrotl(unsignedlongvalue**,intshift);**

unsignedlong_lrotr(unsignedlongvalue**,intshift);**

Routine Required Header Compatibility
_lrotl <stdlib.h> Win 95, Win NT
_lrotr <stdlib.h> Win 95, Win NT

For additional compatibility information, see Compatibility in the Introduction.

Libraries

LIBC.LIB Single thread static library, retail version
LIBCMT.LIB Multithread static library, retail version
MSVCRT.LIB Import library for MSVCRT.DLL, retail version

Return Value

Both functions return the rotated value. There is no error return.

Parameters

value

Value to be rotated

shift

Number of bits to shift value

Remarks

The _lrotl and _lrotr functions rotate value by shift bits. _lrotl rotates the value left. _lrotr rotates the value right. Both functions “wrap” bits rotated off one end of value to the other end.

Example

/* LROT.C */

#include <stdlib.h>
#include <stdio.h>

void main( void )
{
   unsigned long val = 0x0fac35791;

   printf( "0x%8.8lx rotated left eight times is 0x%8.8lx\n",
            val, _lrotl( val, 8 ) );
   printf( "0x%8.8lx rotated right four times is 0x%8.8lx\n",
            val, _lrotr( val, 4 ) );
}

Output

0xfac35791 rotated left eight times is 0xc35791fa
0xfac35791 rotated right four times is 0x1fac3579

Floating-Point Support Routines

See Also   _rotl, _rotr