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From: dennison@telepath.com
Subject: Implementing a stream
Date: 1998/12/15
Message-ID: <7563nn$evn$1@nnrp1.dejanews.com>#1/1
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Date: 1998-12-15T00:00:00+00:00
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I'm looking at implementing a stream class, but I don't think I quite
understand the expected interface. I know I have to implement the following
subprogram:

           procedure Read(
             Stream : in out Root_Stream_Type;
             Item   : out Stream_Element_Array;
             Last   : out Stream_Element_Offset);


But how is it called by default (iaw: from default 'Read and 'Input
routines)? For instance, if my read returns with Last < Item'length, does
read get repeatedly called until Item'length items have been read? Would
returning Last =0 result in a fast busy-loop? If so, I'd think the preferred
method in this instance would be for Read to raise an exception or to block
until there is more data.

--
T.E.D.

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