setbit(9) - NetBSD Manual Pages

SETBIT(9)              NetBSD 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

     bitmap(3), 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.

NetBSD 8.0                     December 4, 2012                     NetBSD 8.0