In article <3c70f302$1@news.povray.org> , "Tom Melly" <tom### [at] tomandlucouk>
wrote:

> Just out of curiousity, and for us non-mac-aware-bods, what sort of bug is
> this and how is it resolved?

Well, like with all out of memory bugs, one has to make sure really everything
checks if malloc didn't return NULL.  Overlooking one in a thousand different
calls to malloc is enough to cause such a problem, given there isn't enough
memory at the right time.

> How is the default allocation set - by the prog., the system or the user? Can
> it change dynamically (i.e. as the prog. is running and requires it)?

Oh, on Macs one can set a upper and lower limit.  Programs are allowed to
request additional memory in the background when they detect they ran out of
memory*, but in general this is not recommended as usually the user has set
the limit for a reason.  POV-Ray for Mac OS is (supposed to come) configured
such that one can render all demo scenes with the default limits, but the
limits I am using are still based on what used to be "big" demo scenes that
came with 3.1g.  Obviously, certain scenes in the advanced folder of 3.5
require much more memory...

Unfortunately Mac OS X no longer has such a flexible allocation scheme
accessible for users unless they want to play with the plain Unix shell :-(

    Thorsten

* The recommended rule for a programmer is that one should use this additional
memory only for a short time.  For example compilers do it when compiling
larger applications - the syntax trees and such can take much more memory than
needed for normal operation, but only for a short time, of course.

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

Visit POV-Ray on the web: http://mac.povray.org

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