Files
calc/have_posscl.c
Landon Curt Noll a31078bbec Remove all RCS @(#) lines and RCS strings
Some folks might think: “you still use RCS”?!?  And we will say,
hey, at least we switched from SCCS to RCS back in … I think it was
around 1994 ... at least we are keeping up! :-) :-) :-)

Logs say that SCCS version 18 became RCS version 19 on 1994 March 18.

RCS served us well.  But now it is time to move on.   And so we are
switching to git.

Calc releases produce a lot of file changes.  In the 125 releases
of calc since 1996, when I started managing calc releases, there
have been 15473 file mods!
2017-05-23 01:33:23 -07:00

90 lines
2.4 KiB
C

/*
* have_posscl - determine if we have a scalar FILEPOS element
*
* 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.
*
* Under source code control: 1996/07/13 12:57:22
* File existed as early as: 1996
*
* chongo <was here> /\oo/\ http://www.isthe.com/chongo/
* Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/
*/
/*
* usage:
* have_posscl
*
* On some systems, FILEPOS is a scalar value on which one can perform
* arithmetic operations, assignments and comparisons. On some systems
* FILEPOS is some sort of union or struct which must be converted into
* a ZVALUE in order to perform arithmetic operations, assignments and
* comparisons.
*
* This prog outputs several defines:
*
* HAVE_FILEPOS_SCALAR
* defined ==> ok to perform arithmetic ops, = and comparisons
* undefined ==> convert to ZVALUE first
*/
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "have_fpos.h"
int
main(void)
{
#if !defined(FILEPOS_NON_SCALAR)
FILEPOS value; /* an FILEPOS to perform arithmatic on */
FILEPOS value2; /* an FILEPOS to perform arithmatic on */
/*
* do some math opts on an FILEPOS
*/
value = (FILEPOS)getpid();
value2 = (FILEPOS)-1;
if (value > (FILEPOS)1) {
--value;
}
#if !defined(_WIN32)
if (value <= (FILEPOS)getppid()) {
--value;
}
#endif
if (value == value2) {
value += value2;
}
value <<= 1;
if (!value) {
printf("/* something for the FILEPOS to do */\n");
}
/*
* report FILEPOS as a scalar
*/
printf("#undef HAVE_FILEPOS_SCALAR\n");
printf("#define HAVE_FILEPOS_SCALAR /* FILEPOS is a simple value */\n");
#else
printf("#undef HAVE_FILEPOS_SCALAR "
"/* FILEPOS is not a simple value */\n");
#endif
/* exit(0); */
return 0;
}