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From: Rudy.Nedved@A.CS.CMU.EDU
Newsgroups: mod.computers.vax
Subject: Re: read() in VAX C 2.1 (VMS 4.2)
Message-ID: <25Feb86.165334.EN0C@A.CS.CMU.EDU>
Date: Tue, 25-Feb-86 16:53:00 EST
Article-I.D.: A.25Feb86.165334.EN0C
Posted: Tue Feb 25 16:53:00 1986
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Nothing int the semantics of Unix or C disallows returning less then the
buffer size. This has always been true for reading a line from a terminal
or getting incoming data from a network.

The only problem that I have come across with VMS C is that for some
reason a read() with a buffer size > 2**16 sometimes returns 0. I
hacked the code to always use a buffer less then 2**16 and the
problem went away....I was porting emacs which likes to do stats on
the file getting filesize X, allocs mem of size X and then does a
read of size X into the memory...it loops if the read is incomplete
but terminates with an error or eof if the read() returns <= 0.

-Rudy