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Date: Sat, 21 Apr 2001 19:25:18 -0400
From: Christopher Faylor <cgf AT redhat DOT com>
To: cygwin-developers-digest-help AT cygwin DOT com, cygwin-developers AT cygwin DOT com,
        newlib AT sources DOT redhat DOT com
Subject: Re: vfscanf in newlib
Message-ID: <20010421192518.E4033@redhat.com>
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In-Reply-To: <3AE1C5B2.B63F2B54@ece.gatech.edu>; from cwilson@ece.gatech.edu on Sat, Apr 21, 2001 at 01:38:58PM -0400

On Sat, Apr 21, 2001 at 01:38:58PM -0400, Charles S. Wilson wrote:
>Didn't somebody already do a threadsafeness audit of newlib?  If so,
>then we don't want to break threadsafeness with these changes.  I'm not
>familiar with threaded code in C; what is neccessary to insure that a
>given function is both reentrant and threadsafe (if a block of code is
>threadsafe it is automatically reentrant, but a reentrant block is not
>necessarily threadsafe, right?)

That's right.

AFAIK, newlib is not guaranteed to be thread safe.

So, I guess that Cygwin is, by extension, not really thread safe either.

I can think of a few functions in cygwin that are not thread safe, in
fact.  The enviroment manipulation is not thread-safe.  I don't believe
that vfork is thread safe.  I'm sure that there are many others.

cgf