netbsd man page for setbit

SETBIT(9)						   BSD Kernel Developer's Manual						 SETBIT(9)

NAME
     setbit -- macros related to bitmaps

SYNOPSIS
     #include <sys/param.h>

     void
     setbit(array, x);

     void
     clrbit(array, x);

     int
     isset(array, x);

     int
     isclr(array, x);

DESCRIPTION
     The setbit family of macros operate with bitmaps, also known as bit arrays.

     In a nutshell, setbit() sets the bit x in array, clrbit() clears it, isset() tests whether x is set, and isclr() returns 1 if x is not set.

EXAMPLES
     The following example declares a buffer of 10 chars, treating it as an array of 80 bits:

	   char buf[10];

	   ...

	   setbit(buf, 12);	   /* set the fifth bit in the second byte */

SEE ALSO
     bitstring(3)

CAVEATS
     The number of valid bits in a given array is assumed to be multiple of CHAR_BIT, the number of bits for smallest object that is not a bit-
     field.

BSD
								   March 1, 2010							       BSD