_rotl, _rotl64, _rotr, _rotr64

Article
06/05/2017

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The latest version of this topic can be found at _rotl, _rotl64, _rotr, _rotr64.

Rotates bits to the left (_rotl) or right (_rotr).

Syntax

  
      unsigned int _rotl(  
   unsigned int value,  
   int shift   
);  
unsigned __int64 _rotl64(  
   unsigned __int64 value,   
   int shift  
);  
unsigned int _rotr(  
   unsigned int value,  
   int shift   
);  
unsigned __int64 _rotr64(  
   unsigned __int64 value,  
   int shift  
);

Parameters

value
Value to be rotated.

shift
Number of bits to shift.

Return Value

The rotated value. There is no error return.

Remarks

The _rotl and _rotr functions rotate the unsigned value by shift bits. _rotl rotates the value left. _rotr rotates the value right. Both functions wrap bits rotated off one end of value to the other end.

Requirements

Routine	Required header
_rotl, _rotl64	<stdlib.h>
_rotr, _rotr64	<stdlib.h>

For more compatibility information, see Compatibility in the Introduction.

Libraries

All versions of the C run-time libraries.

Example

// crt_rot.c  
/* This program shifts values to rotate an integer.  
 */  
  
#include <stdlib.h>  
#include <stdio.h>  
  
int main( void )  
{  
   unsigned val = 0x0fd93;  
   __int64 val2 = 0x0101010101010101;  
  
   printf( "0x%4.4x rotated left three times is 0x%4.4x\n",   
           val, _rotl( val, 3 ) );  
   printf( "0x%4.4x rotated right four times is 0x%4.4x\n",   
           val, _rotr( val, 4 ) );  
  
   printf( "%I64x rotated left three times is %I64x\n",  
           val2, _rotl64( val2, 3 ) );  
   printf( "%I64x rotated right four times is %I64x\n",   
           val2, _rotr64( val2, 4 ) );  
}

Output

0xfd93 rotated left three times is 0x7ec98  
0xfd93 rotated right four times is 0x30000fd9  
101010101010101 rotated left three times is 808080808080808  
101010101010101 rotated right four times is 1010101010101010

.NET Framework Equivalent

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

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