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File caching on Symbian 9.1
| Mon, 2007-12-17 12:45 | |
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Hi Girish |
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| Mon, 2007-12-17 12:45 | |
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Hi Girish |
Forum posts: 1232
You are going to poll the file list of the SD card every 25 ms?
Why?
SD cards are slow... I kind-of doubt you will be able to get the file list in just 25 ms, at least if it is a big memory card.
What is it you are trying to do? It sounds like there is a better solution then polling the SD card every 25 ms....
polling like this would also most likely drain your batteries a lot faster then needed..
Why can't you use any of the file system notifications?
There is an API to tell the file system to give you an event as soon as a file is created or deleted in a specific folder, and can in that way maintain a current list of the files on the SD card.
Forum posts: 78
Hi Thanks for reply
ok I have an external device connected to this SD card and this device writes on this sd card through an interface .....so when the symbian phone (in our case) tries to get the latest files on this sd card which are being updated all the time through a diffferent interface ... it might give the file list in the cache as the list might be cached there. About the System notifications my concern is about to turn off file caching as for example the Symbian API RFs has something called RFs::Get Dir which interacts with the PDD of SD card . Here there might be a logical or a physical cache to read write data from the SD card.
May I know which API you are mentioning ?
Forum posts: 1232
Ah, I see now what you mean, and that you really would have to turn off any cacheing.
The notification API I was thinking about will not help you then. (also part of RFs).
This because I expect the notification only works for files created and deleted through symbian, and what you do here is modify it on a much lower level.
Since you are not using a standard SD card, probably this was not a use case that the symbian engineers were considering when they designed the system...
I'd suggest you write your question here: http://developer.symbian.com/forum/forum.jspa?forumID=4&start=0 and state your usecase where you have special SD card hardware.
There might be more problems then just the cacheing.
Forum posts: 78
Thanks I will try this Symbian forum you suggested as this is a very low level query .