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?RCS: $Id: randbits.U,v 3.0.1.1 1997/02/28 16:19:29 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: randbits.U,v $
?RCS: Revision 3.0.1.1  1997/02/28  16:19:29  ram
?RCS: patch61: added <unistd.h> and <stdlib.h> to the C program test
?RCS:
?RCS: Revision 3.0  1993/08/18  12:09:38  ram
?RCS: Baseline for dist 3.0 netwide release.
?RCS:
?X:
?X:	This unit has been somewhat made obsolete with creation of the
?X:	randfunc function (which finds out how to generate random
?X:	numbers between 0 and 1.
?X:
?MAKE:randbits: cat rm Myread cc i_unistd i_stdlib
?MAKE:	-pick add $@ %<
?S:randbits:
?S:	This variable contains the eventual value of the RANDBITS symbol,
?S:	which indicates to the C program how many bits of random number
?S:	the rand() function produces.
?S:.
?C:RANDBITS:
?C:	This symbol contains the number of bits of random number the rand()
?C:	function produces.  Usual values are 15, 16, and 31.
?C:.
?H:#define RANDBITS $randbits		/**/
?H:.
: check for size of random number generator
echo " "
case "$randbits" in
'')
	echo "Checking to see how many bits your rand function produces..." >&4
	$cat >try.c <<EOCP
#$i_unistd I_UNISTD
#$i_stdlib I_STDLIB
#include <stdio.h>
#ifdef I_UNISTD
#  include <unistd.h>
#endif
#ifdef I_STDLIB
#  include <stdlib.h>
#endif
EOCP
	$cat >>try.c <<'EOCP'
main()
{
	register int i;
	register unsigned long tmp;
	register unsigned long max = 0L;

	for (i = 1000; i; i--) {
		tmp = (unsigned long)rand();
		if (tmp > max) max = tmp;
	}
	for (i = 0; max; i++)
		max /= 2;
	printf("%d\n",i);
}
EOCP
	if $cc try.c -o try >/dev/null 2>&1 ; then
		dflt=`try`
	else
		dflt='?'
		echo "(I can't seem to compile the test program...)"
	fi
	;;
*)
	dflt="$randbits"
	;;
esac
rp='How many bits does your rand() function produce?'
. ./myread
randbits="$ans"
$rm -f try.c try