RTOS/AM5726: FATFS flags details

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Hi, Eric.

Thanks for the response.

However, something is missing.

The ff.h header defines the following file access flags:

/* File access control and file status flags (FIL.flag) */

#define FA_READ 0x01
#define FA_WRITE 0x02
#define FA_OPEN_EXISTING 0x00
#define FA_CREATE_NEW 0x04
#define FA_CREATE_ALWAYS 0x08
#define FA_OPEN_ALWAYS 0x10
#define _FA_MODIFIED 0x20
#define _FA_DIRTY 0x40

There is no definition for FA_OPEN_APPEND here.

Additionally, the link you've posted doesn't define _FA_MODIFIED and _FA_DIRTY.

I want to be able to link between those definitions and the flags as defined for C standard. We use GNU build tools, if you go to the file 

C:\ti\gcc-arm-none-eabi-6-2017-q1-update\arm-none-eabi\include\sys\_default_fcntl.h

You'll see that:

#define _FOPEN (-1) /* from sys/file.h, kernel use only */

#define _FREAD 0x0001 /* read enabled */
#define _FWRITE 0x0002 /* write enabled */
#define _FAPPEND 0x0008 /* append (writes guaranteed at the end) */
#define _FMARK 0x0010 /* internal; mark during gc() */
#define _FDEFER 0x0020 /* internal; defer for next gc pass */
#define _FASYNC 0x0040 /* signal pgrp when data ready */
#define _FSHLOCK 0x0080 /* BSD flock() shared lock present */
#define _FEXLOCK 0x0100 /* BSD flock() exclusive lock present */
#define _FCREAT 0x0200 /* open with file create */
#define _FTRUNC 0x0400 /* open with truncation */
#define _FEXCL 0x0800 /* error on open if file exists */
#define _FNBIO 0x1000 /* non blocking I/O (sys5 style) */
#define _FSYNC 0x2000 /* do all writes synchronously */
#define _FNONBLOCK 0x4000 /* non blocking I/O (POSIX style) */
#define _FNDELAY _FNONBLOCK /* non blocking I/O (4.2 style) */
#define _FNOCTTY 0x8000 /* don't assign a ctty on this open */

#define O_ACCMODE (O_RDONLY|O_WRONLY|O_RDWR)

/*
* Flag values for open(2) and fcntl(2)
* The kernel adds 1 to the open modes to turn it into some
* combination of FREAD and FWRITE.
*/
#define O_RDONLY 0 /* +1 == FREAD */
#define O_WRONLY 1 /* +1 == FWRITE */
#define O_RDWR 2 /* +1 == FREAD|FWRITE */
#define O_APPEND _FAPPEND
#define O_CREAT _FCREAT
#define O_TRUNC _FTRUNC
#define O_EXCL _FEXCL
#define O_SYNC _FSYNC

Hi,

The FATFS is open source and keeps updating. In TI processor SDK, we used 0.12 release as seen from ff.h. The latest FATFS is 0.13b, from release note: elm-chan.org/.../updates.txt

R0.12a (July 10, 2016)
Added support for creating exFAT volume with some changes of f_mkfs().
Added a file open method FA_OPEN_APPEND. An f_lseek() following f_open() is no longer needed.

So the FA_OPEN_APPEND was added later. That is why it is not there in the TI version FATFS. For the
#define _FA_MODIFIED 0x20
#define _FA_DIRTY 0x40
It was removed from the latest FATFS, I didn't find the history.

So with the current TI version, you need the relationship of _FA_MODIFIED and _FA_DIRTY to POSIX C? How do you want to use this relation? Like a common high level API, to translate into different mode in either FATFS or POSIX?

Regards, Eric

Hi, Eric.
You are right, I want to understand the relation of _FA_MODIFIED, _FA_DIRTY to standard POXIS high level file API, like fopen(...).
Thanks

Anatoly,

Those two flags are from FATFS open source code, I asked the question on the FATFS forum and will update here.

Regards, Eric