Filing Systems




FileCore has been updated to provide access to larger discs and to avoid limitations of the earlier interfaces.

FileCore_DiscOp64 (&4054C)
On entry
   R1 = flags:
               bits 0-3 - reason code (see FileCore_DiscOp)
               bits 4-7 - options (see FileCore_DiscOp)
               bits 8-31 - reserved, must be 0
   R2 = pointer to disc address buffer :
         +0 = drive and flags:
               bits 0-7 - drive number (only drives 0-7 supported)
               bits 8-31 - reserved, must be 0
         +4 = disc byte address (low 32 bits)
         +8 = disc byte address (high 32 bits)
   R3 = pointer to buffer to use
   R4 = length of buffer
   R5 = pointer to alternative disc record, or 0 if unused
   R6 = cache handle, if relevant to the reason code
   R8 = pointer to FileCore instance private word
On exit
   R1, R2 preserved
   R2 block updated to next disc byte address
   R3 = pointer to end of used buffer
   R4 = number of bytes not transferred

This SWI is an extended form of FileCore_DiscOp which avoids limited 26bit interfaces. It is implemented internally within FileCore using the existing calls, thus the limitations are identical to those of the FileCore_DiscOp and FileCore_SectorOp calls. Future versions of the module may remove these limitations.

FileCore_Features (&4054D)
On entry
On exit
   R0 = feature flags :
         bit 0 - FileCore modules should use new error scheme
         bits 1-31 - reserved

This SWI is used to read the feature set of the FileCore module. If it returns an error, the feature flags should be assumed to be 0. At present FileCore does not support the extended error scheme and bit 0 will be clear. The scheme will be documented in a future release.

This documentation is copyright 3QD Developments Ltd 2013 and may not be reproduced or published in any form without the copyright holders permission. RISC OS is subject to continuous development and improvement as such all information is reproduced by 3QD Developments Ltd in good faith and is believed to be correct at the time of publication E&OE. 3QD Developments Ltd cannot accept any liability for any loss or damage arising from the use of any information provided as part of the RISC OS Documentation.

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