bitset(3C)
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bitset $builtin function
Set a bit to either 0 or 1.
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Calling Sequence
#include <bit.h>
void bitset();
short *ptr;
int offset, value;
bitset(ptr, offset, value);
or
$builtin void bitset();
short *ptr;
int offset, value;
bitset(ptr, offset, value);
Description
The bitset function sets the bit specified by a word pointer,
ptr, and a non-negative bit offset, offset, to 0 if the least
significant bit of value is 0; otherwise, the bit is set to 1.
Note that the most significant bit in the 16-bit word pointed to
by ptr is at offset 0, and the least significant bit is at offset
15. If the offset is negative, the bitset routine may cause an
error.
The first calling sequence noted above uses a function call. The
second might generate smaller or faster code, but may not run
under other C compilers.
The include file bit.h defines this function.
Returns
The bitset function does not return anything.
Related Functions
See also the bitvalue and bitszbo functions.
Example
DG/UX 4.00 Page 1
Licensed material--property of copyright holder(s)
bitset(3C)
/* Program test for the bitset() function */
#include <bit.h>
#include <stdio.h>
short s;
main() {
s = 3; /* bits 15 & 14 are 1 */
bitset(&s, 0, 1); /* set bit 0 to 1 */
bitset(&s, 15, 0); /* set bit 15 to 0 */
(void) printf("s = %hx (hexadecimal)\n", s);
}
The above program produces the output
s = 8002 (hexadecimal)
DG/UX 4.00 Page 2
Licensed material--property of copyright holder(s)