_lrotl, _lrotr

项目
07/25/2011

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

unsigned long _lrotl(
   unsigned long value,
   int shift 
);
unsigned long _lrotr(
   unsigned long value,
   int shift 
);

Parameters

value
Value to be rotated.
shift
Number of bits to shift value.

Return Value

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

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.

Requirements

Routine	Required header
_lrotl	<stdlib.h>
_lrotr	<stdlib.h>

For more compatibility information, see Compatibility in the Introduction.

Libraries

All versions of the C run-time libraries.

Example

// crt_lrot.c

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

int 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

.NET Framework Equivalent

Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.

通过