Masking

[Mike Copeland]

How do I mask a portion of an int that's been constructed from several
data fields? That is, I have an int value that contains several values;
bits 10-15 have something I want to isolate and use. I know I can bit-
shift back and forth, but is there a way to mask out these bits and use
them as an integer value? TIA

[Leor Zolman]

On Wed, 4 Feb 2004 21:30:01 -0700, mr*******@cox.net (Mike Copeland)
wrote:

How do I mask a portion of an int that's been constructed from several
data fields? That is, I have an int value that contains several values;
bits 10-15 have something I want to isolate and use. I know I can bit-
shift back and forth, but is there a way to mask out these bits and use
them as an integer value? TIA

Use the binary & (bitwise and) operator:

unsigned int bits = 0xabcd;
unsigned int something = (bits >> 10) & 0x3f; // get bits 10-15

(The above assumes the low-order bit is called "bit 0")
-leor