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Date:	Sun, 07 Jun 2009 14:45:54 +0200
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From:	Margit Schubert-While <margitsw AT t-online DOT de>
Subject:	fcntl (locking) bug?
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 >> This is 1.5.25 but also happens on earlier versions.
 >> It would appear that placing a shared read lock
 >> on a file open for input/output is preventing the
 >> the process itself from writing.

Corinna scribeth :
 > Cygwin up to release 1.5.25 implements fcntl locks using Windows file
 > locking calls.  Windows semantics disallow write access to a shared lock
 > for all processes, even the one setting up the first lock.  Only an
 > exclusive lock allows the locking process to write.

Hmm. Unfortunate and not intuitive. Hmm - fcntl is in the
Cygwin SUSV3 compat list 
-http://cygwin.com/cygwin-api/compatibility.html#std-susv3  ?
SUSV3 mandates this functionality.
Maybe an addendum somewhere or an entry
in http://cygwin.com/cygwin-api/std-notes.html ?

Margit 


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