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dlopen() performance on Mac OS X?
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From: Simon Connah <simon.con...@googlemail.com>
Newsgroups: comp.unix.programmer
Date: Sat, 4 Jul 2009 03:04:19 +0100
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Subject: Re: dlopen() performance on Mac OS X?
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On 2009-07-04 02:07:39 +0100, Eric Sosman <esos...@ieee-dot-org.invalid> said:
> So I imagine you're worried about the use of the functions
> residing in the library to which dlopen() gives you access.
> There are two (potential) penalties I can think of: First, each
> call must be indirect through a function pointer variable rather
> than direct to an address known at link time, and second, it may
> be that the address-space shenanigans with which a particular
> system supports dynamic linking tend to punish MMU's and TLB's
> and the like.
Yes, sorry I should have been more specific. I was using dlopen() as a
short hand for describing the whole system rather than just the
function call itself.
What I was really trying to get at was whether the dlopen / dlsym /
dlclose system added any extra over head on top of what the system
already uses for dynamic linking? Obviously there is going to be a
small performance loss due to needing to search for the library and
possibly deciding which is the correct library to load but other than
that is there any difference?
Or is it the same implementation just with a developer accessable interface?
Hopefully that made a bit more sense.
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