/usr/share/calc/help/str is in apcalc-common 2.12.4.4-3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
| 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 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 | NAME
    str - convert some types of values to strings
SYNOPSIS
    str(x)
TYPES
    x		null, string, real or complex number
    return	string
DESCRIPTION
    Convert a value into a string.
    If x is null, str(x) returns the string "".
    If x is a string, str(x) returns x.
    For real or complex x, str(x) returns the string representing x
    in the current printing mode; configuration parameters affecting
    this are "mode", "mode2", "display", "outround", "tilde", "leadzero",
EXAMPLE
    ; str("")
	    ""
    ; str(null())
	    ""
    ; print str(123), str("+"), str(4i), str("is the same as"), str(123+4i)
    123 + 4i is the same as 3+4i
    ; base2(16),
    ; print str(23209)
    23209 /* 0x5aa9 */
LIMITS
    none
LINK LIBRARY
    void math_divertio();
    qprintnum(NUMBER *x, int outmode);
    char *math_getdivertedio();
    math_divertio();
    comprint(COMPLEX *x);
    char *math_getdivertedio();
SEE ALSO
    base, base2, config
## Copyright (C) 1999-2006  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: str,v 30.1 2007/03/16 11:10:42 chongo Exp $
## @(#) $Source: /usr/local/src/cmd/calc/help/RCS/str,v $
##
## Under source code control:	1995/10/05 04:52:27
## 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/
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