RL02 version of UNIX6?

Paul Koning paulkoning at comcast.net
Thu Feb 2 12:50:19 CST 2017


> On Feb 2, 2017, at 1:41 PM, Noel Chiappa <jnc at mercury.lcs.mit.edu> wrote:
> 
>> From: Phil Blundell
> 
>> I suspect it would probably not be all that hard to write some
>> sort of preprocessor to convert such code
> 
> Really? Check out:
> 
>  http://minnie.tuhs.org/cgi-bin/utree.pl?file=V6/usr/sys/ken/pipe.c  
> 
> (Needless to say, none of the 'int *' things are actually pointers to
> integers!)
> 
> In particular, what will lines like this:
> 
>  sleep(ip+2, PPIPE);
> 
> do, depending on what 'ip' is declared as?

If "ip" is an int *, it would pass the address in ip plus 2 * 2.  If ip is actually the address of some struct, then hopefully that address offset by 4 is a meaningful address.  I'm guessing that the 2 in there represents sizeof(foo)/sizeof(int).  Right?

	paul




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