From:	Tom Burgess <Tom_Burgess AT bc DOT sympatico DOT ca>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Allegro Question
Date:	Sun, 30 Mar 1997 01:29:08 -0700
Organization:	BCTEL Advanced Communications
Lines:	18
Message-ID:	<333E2454.6875@bc.sympatico.ca>
References:	<19970329000031723 DOT AAA166 AT ns1 DOT megsinet DOT net>
NNTP-Posting-Host:	pntn02m01-41.bctel.ca
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To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Paul Schmidt wrote:
> 
> How do you use the following?
> Do you bitwise AND 2 constants together to see if they are both pressed?
> Like if (KB_SHIFT_FLAG & KB_CTRL_FLAG)
> printf("Shift and CTRL Pressed\n");
> ?Close, but what you want is
	if ((KB_SHIFT_FLAG & key_shifts) && (KB_CTRL_FLAG & key_shifts))
		printf("Shift and CTRL Pressed\n");

where key_shifts contains a bunch of flags. Note that the bitwise & is
used to extract the flag, and the logical && is used to combine them
so that both must be non-zero for the test to pass. The extra parenthesis
will be appreciated by future maintainers of your code.

	regards, tom

	regards, tom.

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