NetNews Offline 2/NetNews Offline Volume 2.iso/news/comp/lang/c++-part1/6355

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From: Leonid Ilyevsky <[e-mail]>
Newsgroups: comp.lang.c++
Subject: Threads and pipes
Date: Fri, 09 Feb 1996 10:33:21 -0500
Organization: NYNEX S&T
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Help ! I need threads in my program to talk to each other through the
pipe. I don't want to use regular Unix pipes (I tested this approach,
it works fine) because that would involve an overhead of system calls.
However, I want all the functionality of the pipe, that is:

1. Ability to use iostream methods.
2. The writing thread should be able to:
   (a) write any information to the pipe like to any stream (see #1)
   (b) close the pipe after it's done
3. The reading thread should be able to:
   (a) read from the pipe like from any stream (see again #1)
   (b) be blocked if there is nothing to read at the moment, but the
       pipe's writing end is not closed yet
   (c) be waked up when something new was written to the pipe
   (d) get EOF if pipe's writing end is closed and everything is read

I tried strstream object, but it has only some of these features.
It has #1 (#2a + #3a), but there is no such thing as #2b. The #3b is
not there, it gets EOF when everything is read, and the writing thread
is completely confused after that, so don't even ask about #3c.
I learned from the manual that this problem can be solved by overriding
some virtual functions in streambuf base class. But I wonder if there
is something ready to use.
   Please, reply by E-mail.
--

      Leonid Ilyevsky                       NYNEX Science and Technology
E-mail: [e-mail]                  500 Westchester Ave.
Phone:[phone] Fax:[phone]       White Plains, NY  10604