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_lrotl, _lrotr

 

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

Syntax

  
      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.

See Also

Floating-Point Support
_rotl, _rotl64, _rotr, _rotr64