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Path: utzoo!linus!faron!meister
From: meister@faron.UUCP (Philip W. Servita)
Newsgroups: net.lang.c
Subject: Re: C Input Question?
Message-ID: <247@faron.UUCP>
Date: Mon, 4-Mar-85 11:26:31 EST
Article-I.D.: faron.247
Posted: Mon Mar  4 11:26:31 1985
Date-Received: Sun, 17-Mar-85 19:13:10 EST
References: <1556@ritcv.UUCP> <155@cci-bdc.UUCP>
Reply-To: meister@faron.UUCP (Philip W. Servita)
Distribution: net
Organization: The MITRE Coporation, Bedford, MA
Lines: 45

>> I am working an a very simple game using graphics text with a
>> GiGi terminal.  I am having a big problem with the input.  When
>> I get to a read, or any input statment, in C, everything stops
>> and waits for the input.
>> 
>[text cut for brevity. Scott wants non-blocking I/O, that is "read if
>data, but don't wait for data.]
>>
>> Is there an easy way to do this in C.  
>> I am doing this on a VAX running 4.2 if that makes a difference.  
>>
>> scott hossler
>> rochester!ritcv!sah9577


i did this once i a game program also. try the following:

#include <sgtty.h>

...

char 
inkey()

{

   long charwaiting;
   char getchar();

   ioctl(0,FIONREAD,&charwaiting);

   if(charwaiting) return(getchar());   
 
   return((char) 0);

}

returns the next character on the stdin stream if there is one, 0 otherwise.
this will only work in cbreak or raw mode. look up tty(4) for details.

                                        -the venn buddhist
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