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?RCS: $Id: d_safebcpy.U,v 3.0 1993/08/18 12:06:58 ram Exp $
?RCS:
?RCS: Copyright (c) 1991-1993, Raphael Manfredi
?RCS: 
?RCS: You may redistribute only under the terms of the Artistic Licence,
?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 Licence; a copy of which may be found at the root
?RCS: of the source tree for dist 3.0.
?RCS:
?RCS: $Log: d_safebcpy.U,v $
?RCS: 
?RCS: Copy "abcde..." string to char abc[] so that gcc doesn't 
?RCS: try to store the string in read-only memory.
?RCS: 
?RCS: Revision 3.0  1993/08/18  12:06:58  ram
?RCS: Baseline for dist 3.0 netwide release.
?RCS:
?MAKE:d_safebcpy: cat d_bcopy +cc +ccflags +libs rm Oldconfig Setvar
?MAKE:	-pick add $@ %<
?S:d_safebcpy:
?S:	This variable conditionally defines the HAS_SAFE_BCOPY symbol if
?S:	the bcopy() routine can do overlapping copies.
?S:.
?C:HAS_SAFE_BCOPY (SAFE_BCOPY):
?C:	This symbol, if defined, indicates that the bcopy routine is available
?C:	to copy potentially overlapping memory blocks. Otherwise you should
?C:	probably use memmove() or memcpy(). If neither is defined, roll your
?C:	own version.
?C:.
?H:#$d_safebcpy HAS_SAFE_BCOPY	/**/
?H:.
?LINT: set d_safebcpy
: can bcopy handle overlapping blocks?
?X: assume the worst
val="$undef"
case "$d_bcopy" in
"$define")
	echo " "
	echo "Checking to see if your bcopy() can do overlapping copies..." >&4
	$cat >foo.c <<'EOCP'
main()
{
char buf[128], abc[128];
char *b;
int len;
int off;
int align;
bcopy("abcdefghijklmnopqrstuvwxyz0123456789", abc, 36);

for (align = 7; align >= 0; align--) {
	for (len = 36; len; len--) {
		b = buf+align;
		bcopy(abc, b, len);
		for (off = 1; off <= len; off++) {
			bcopy(b, b+off, len);
			bcopy(b+off, b, len);
			if (bcmp(b, abc, len))
				exit(1);
		}
	}
}
exit(0);
}
EOCP
	if $cc foo.c -o safebcpy $ccflags $libs >/dev/null 2>&1 ; then
		if ./safebcpy 2>/dev/null; then
			echo "Yes, it can."
			val="$define"
		else
			echo "It can't, sorry."
		fi
	else
		echo "(I can't compile the test program, so we'll assume not...)"
	fi
	;;
esac
$rm -f foo.* safebcpy core
set d_safebcpy
eval $setvar