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Message-ID: <000501c1a9a3$47d613a0$010310ac@lyoncleitienne>
From: "Christophe LEITIENNE" <cleitienne AT wanadoo DOT fr>
To: "egor duda" <cygwin AT cygwin DOT com>
Subject: cygipc shmat bug
Date: Wed, 30 Jan 2002 16:32:06 +0100
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Hi all,
I've noticed some problems using shared memory with cygipc, which don't seem
to be present in the mailing list archives.
I'm running cygwin 1.3.9 with cygipc 1.11 on a W2K machine.

SYMPTOMS
If you run multiple times a simple app that attaches a shared memory segment
(with shmat), some attachments fail (shmat return -1, errno: invalid
argument).

TO REPRODUCE THIS BEHAVIOR:
- open a cygwin bash shell
- launch "ipctest.exe h" to create a shared memory segment
- call "ipcs" to know the shmid of the segment you just created
- then run "while true; do ipctest.exe h a <shmid>; done"
You'll see that some of the attachments fail with "shmat : Invalid argument"

Well, I'm not sure this is really a new bug, since I saw that shmat uses
mmap and mmap is buggy, right ?

Best Regards,

Christophe LEITIENNE


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