[Lazarus] Using Lazarus on Embedded Linux?
Henry Vermaak
henry.vermaak at gmail.com
Mon Sep 27 13:56:45 CEST 2010
On 27/09/10 12:41, Mark Morgan Lloyd wrote:
> Henry Vermaak wrote:
>
>>> The first of those can at least be initiated using a sync() call, and
>>> it's reasonable to assume that a filesystem designed for the purpose
>>> won't get screwed if the driver finds it can no longer talk to the
>>> storage device. However if the storage device itself is susceptible to
>>> errors caused by power removal that is far more sinister.
>>
>> The only delay I can see (after fsync) would be due to the hardware
>> cache of the disk in use (or a defective drive). On linux you can call
>> hdparm to flush on-disk caches.
>
> But is hdparm fully supported by external Flash cards, and does it
> return before or after data is guaranteed to be filly committed?
This is a red herring (sorry, my mistake). Compact flash cards (and
other removable media) are block devices, they have firmware that do
this flash to block emulation. I realise now that Michael meant that
some cf cards have crappy firmware that can't handle power cuts. There
isn't much you can do about that, but choose a good cf card or usb stick.
Henry
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