What is the Memory Mapped File Class?

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trycatchthis
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What is the Memory Mapped File Class?

Post by trycatchthis »

I searched for such a class with no luck.
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upCASE
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Post by upCASE »

Hi!
Not sure what you want to do, but have a look at wxMemoryFSHandler.
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trycatchthis
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Post by trycatchthis »

You use memory mapped files so that instead of allocating a big chunck of ram you use a file.

They make a file look like if it was loded in ram.
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upCASE
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Post by upCASE »

Hi!
For that purpose try using wxMemoryFSHandler with a wxFile. There is no wxMemoryFile class as far as I remember.
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Ryan Norton
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Post by Ryan Norton »

upCASE wrote:Hi!
For that purpose try using wxMemoryFSHandler with a wxFile. There is no wxMemoryFile class as far as I remember.
Hey, I've got one for wikiserver I can put up if there's demand for it....
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mjs
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Post by mjs »

It'd be nice if you could upload it. Until now I'm unsure if it's really useful because on 32 bit platforms you have an effective 2G limit which seems too restrictive for a file API ...

Regards,
Mark
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trycatchthis
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Post by trycatchthis »

I dont know if wxMemoryFSHandler is what i am looking for.

Does it store the data in memory?
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upCASE
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Post by upCASE »

Well, I'll just quote the docs...
wxMemoryFSHandler::AddFile
Add file to list of files stored in memory. Stored data (bitmap, text or raw data) will be copied into private memory stream and available under name "memory:" + filename.
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Ryan Norton
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Post by Ryan Norton »

upCASE wrote:Well, I'll just quote the docs...
wxMemoryFSHandler::AddFile
Add file to list of files stored in memory. Stored data (bitmap, text or raw data) will be copied into private memory stream and available under name "memory:" + filename.
All a memory mapped file is using

CreateFileMapping
MapViewOfFile
UnmapViewOfFile
CloseHandle

on Win32

and mmap and munmap on POSIX (OSX I think too).
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trycatchthis
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Post by trycatchthis »

can you define "private memory stream"
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