Rotate bits to the left (_rotl) or right (_rotr).
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 _rotl64(
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 | Compatibility |
| _rotl, _rotl64 | <stdlib.h> | Win 98, Win Me, Win NT, Win 2000, Win XP |
| _rotr, _rotr64 | <stdlib.h> | Win 98, Win Me, Win NT, Win 2000, Win XP |
For additional 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
See Also
Floating-Point Support Routines | _lrotl | Run-Time Routines and .NET Framework Equivalents