?RCS: $Id$
?RCS:
?RCS: Copyright (c) 1991-1997, 2004-2006, Raphael Manfredi
?RCS:
?RCS: You may redistribute only under the terms of the Artistic License,
?RCS: as specified in the README file that comes with the distribution.
?RCS: You may reuse parts of this distribution only within the terms of
?RCS: that same Artistic License; a copy of which may be found at the root
?RCS: of the source tree for dist 4.0.
?RCS:
?RCS: $Log: d_shmat.U,v $
?RCS: Revision 3.0.1.3  1995/07/25  14:04:23  ram
?RCS: patch56: use findhdr to find <sys/shm.h>, to get the right one (ADO)
?RCS:
?RCS: Revision 3.0.1.2  1994/05/13  15:18:56  ram
?RCS: patch27: added new symbol HAS_SHMAT_PROTOTYPE (ADO)
?RCS:
?RCS: Revision 3.0.1.1  1994/05/06  14:54:18  ram
?RCS: patch23: new Shmat_t symbol to declare return type of shmat()
?RCS:
?RCS: Revision 3.0  1993/08/18  12:07:18  ram
?RCS: Baseline for dist 3.0 netwide release.
?RCS:
?MAKE:d_shmat shmattype d_shmatprototype: Trylink Setvar cat
?MAKE:	-pick add $@ %<
?S:d_shmat:
?S:	This variable conditionally defines the HAS_SHMAT symbol, which
?S:	indicates to the C program that the shmat() routine is available.
?S:.
?S:shmattype:
?S:	This symbol contains the type of pointer returned by shmat().
?S:	It can be 'void *' or 'char *'.
?S:.
?S:d_shmatprototype:
?S:	This variable conditionally defines the HAS_SHMAT_PROTOTYPE
?S:	symbol, which indicates that sys/shm.h has a prototype for
?S:	shmat.
?S:.
?C:HAS_SHMAT:
?C:	This symbol, if defined, indicates that the shmat() routine is
?C:	available to attach a shared memory segment to the process space.
?C:.
?C:Shmat_t:
?C:	This symbol holds the return type of the shmat() system call.
?C:	Usually set to 'void *' or 'char *'.
?C:.
?C:HAS_SHMAT_PROTOTYPE:
?C:	This symbol, if defined, indicates that the sys/shm.h includes
?C:	a prototype for shmat().  Otherwise, it is up to the program to
?C:	guess one.  Shmat_t shmat _((int, Shmat_t, int)) is a good guess,
?C:	but not always right so it should be emitted by the program only
?C:	when HAS_SHMAT_PROTOTYPE is not defined to avoid conflicting defs.
?C:.
?H:#$d_shmat HAS_SHMAT		/**/
?H:#define Shmat_t $shmattype	/**/
?H:#$d_shmatprototype HAS_SHMAT_PROTOTYPE	/**/
?H:.
?LINT:set d_shmat d_shmatprototype
: see if shmat exists
$cat >try.c <<EOC
#include <sys/shm.h>
int main(void)
{
	static int id, flags;
	static void *addr;
	(void) shmat(id, addr, flags);
	return 0;
}
EOC
cyn=shmat
set d_shmat 
eval $trylink

case "$d_shmat" in
"$define")
	$cat >try.c <<EOC
#include <sys/shm.h>
extern void shmat(void);
int main(void) { return 0; }
EOC
	cyn="whether <sys/shm.h> contains the shmat() prototype"
	set val
	eval $trylink
	case "$val" in
	"$define")	val="$undef";;
	*)		val="$define";;
	esac
	;;
*)	val="$undef";;
esac

set d_shmatprototype
eval $setvar

case "$d_shmat" in
"$define")
	echo " "
	echo "Looking for the correct shmat prototype..." >&4
	;;
esac

case "$d_shmat" in
"$define")
	$cat >try.c <<EOC
#include <sys/shm.h>
extern void *shmat(int, const void *, int);
int main(void) { return 0; }
EOC
	set val
	eval $trylink
	;;
esac

case "$d_shmat" in
"$define")
	$cat >try.c <<EOC
#include <sys/shm.h>
extern void *shmat(int, void *, int);
int main(void) { return 0; }
EOC
	set val
	eval $trylink
	case "$val" in
	"$define") shmattype='void *';;
	esac
	;;
esac

case "$d_shmat" in
"$define")
	$cat >try.c <<EOC
#include <sys/shm.h>
extern char *shmat(int, char *, int);
int main(void) { return 0; }
EOC
	set val
	eval $trylink
	case "$val" in
	"$define") shmattype='char *';;
	esac
	;;
esac

case "$d_shmat" in
"$define") echo "shmat() returns $shmattype";;
esac