/usr/share/calc/help/highbit is in apcalc-common 2.12.4.4-3.
This file is owned by root:root, with mode 0o644.
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| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 | NAME
    highbit - index of highest bit in binary representation of integer
SYNOPSIS
    highbit(x)
TYPES
    x		nonzero integer
    return	integer
DESCRIPTION
    If x is a nonzero integer, highbit(x) returns the index of the
    highest bit in the binary representation of abs(x).	 Equivalently,
    highbit(x) = n if 2^n <= abs(x) < 2^(n + 1);  the binary
    representation of x then has n + 1 digits.
EXAMPLE
    ; print highbit(2), highbit(3), highbit(4), highbit(-15), highbit(2^27)
    1 1 2 3 27
LIMITS
    none
LINK LIBRARY
    LEN zhighbit(ZVALUE x);
SEE ALSO
    lowbit, digits
## Copyright (C) 1999  Landon Curt Noll
##
## Calc is open software; you can redistribute it and/or modify it under
## the terms of the version 2.1 of the GNU Lesser General Public License
## as published by the Free Software Foundation.
##
## Calc is distributed in the hope that it will be useful, but WITHOUT
## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
## or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU Lesser General
## Public License for more details.
##
## A copy of version 2.1 of the GNU Lesser General Public License is
## distributed with calc under the filename COPYING-LGPL.  You should have
## received a copy with calc; if not, write to Free Software Foundation, Inc.
## 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
##
## @(#) $Revision: 30.1 $
## @(#) $Id: highbit,v 30.1 2007/03/16 11:10:42 chongo Exp $
## @(#) $Source: /usr/local/src/cmd/calc/help/RCS/highbit,v $
##
## Under source code control:	1995/10/03 10:40:02
## File existed as early as:	1995
##
## chongo <was here> /\oo/\	http://www.isthe.com/chongo/
## Share and enjoy!  :-)	http://www.isthe.com/chongo/tech/comp/calc/
 |