4.3BSD-UWisc/man/cat3/bit.3f

BIT(3F)             UNIX Programmer's Manual              BIT(3F)



NAME
     bit - and, or, xor, not, rshift, lshift bitwise functions

SYNOPSIS
     (intrinsic) function and (word1, word2)

     (intrinsic) function or (word1, word2)

     (intrinsic) function xor (word1, word2)

     (intrinsic) function not (word)

     (intrinsic) function rshift (word, nbits)

     (intrinsic) function lshift (word, nbits)

DESCRIPTION
     These bitwise functions are built into the compiler and
     return the data type of their argument(s).  Their arguments
     must be integer or logical values.

     The bitwise combinatorial functions return the bitwise
     ``and'' (and), ``or'' (or), or ``exclusive or'' (xor) of two
     operands.  Not returns the bitwise complement of its
     operand.

     _L_s_h_i_f_t, or _r_s_h_i_f_t with a negative _n_b_i_t_s, is a logical left
     shift with no end around carry.  _R_s_h_i_f_t, or _l_s_h_i_f_t with a
     negative _n_b_i_t_s, is an arithmetic right shift with sign
     extension.  No test is made for a reasonable value of _n_b_i_t_s.

     These functions may be used to create a variety of general
     routines, as in the following statement function defini-
     tions:

        integer bitset, bitclr, getbit, word, bitnum

        bitset( word, bitnum ) = or(word,lshift(1,bitnum))
        bitclr( word, bitnum ) = and(word,not(lshift(1,bitnum)))
        getbit( word, bitnum ) = and(rshift(word,bitnum),1)

FILES
     These functions are generated in-line by the f77 compiler.












Printed 12/27/86         April 30, 1986                         1