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Re: What's left to do? [LONG]

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Sam Tregar
March 22, 2000 10:23
Re: What's left to do? [LONG]
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On Wed, 22 Mar 2000, Dan Sugalski wrote:

> >My current understanding is that in a threaded program all code that
> >accesses global data need to use some kind of explicit locking.  Thus, any
> >module that accesses global data of any kind is not thread safe and needs
> >modification to be thread safe.  Is this accurate?
> Yup, that's accurate. Global data, in this case, isn't just package 
> variables, but any variable that might be visible, including lexicals and 
> things inside objects and such.

So, essentially, "testing" for thread safety boils down to a process of
visual inspection.  Correct?

As far as figuring out what's safe and what's not, could you explain how
lexicals can be unsafe?  Are there global variables that *are* safe, like
$_ and @_ for example, or are they all in need of locks?

RTFM?  Which one?


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