So instead of using the standard linux open(), write(), close() we have to use le_fs_Open(), le_fs_Write(), le_fs_Close(). They aren’t working though. le_fs_Open() will return a file descriptor, but write will not write to files. I’ve given my application permission to access the parent directories in the .adef. Any help is appreciated.

Why don’t you use standard linux api if it is working fine?

Standard linux calls aren’t working. R13, legato 19.11.2 and 20.04.0

I rewrote with fopen(), and it fails.

Other user does not find problem, you can have a look here: [image] Write value in mangOH /sys files mangOH Yellow Blockquote When using unsandboxed application, you need to specify the full path when fopen() . I did that, but i had the same error (Bad file descriptor). But I tried (in unsandboxed mode) to use open instead of fopen and write instead of fprintf and it worked ! If anyone is interested, here is my code: #include "interfaces.h" #include "legato.h" #include #include #include #include COMPONENT_INIT { int rc; int fp = open("/sys/bus/i2c/devi…

open(), etc. are working for me. Firmware Version: SWI9X06Y_02.35.02.00 5208b3 jenkins 2020/06/10 00:30:12. Legato Version: 19.11.2_625c7d1acfd1ca45b2dbe189b4cb1ce7_modified

If your application is sandboxed, you won’t have access to much of the file system. If you unsandbox your application (by adding a line “sandboxed: false” to your .adef file), then you’ll have access to all of the file system. It doesn’t matter whether you use fopen() or open(). They should both work. Of course, it’s better to run sandboxed. There are some features in the Component.cdef and .adef files that allow you to remain sandboxed but still have access to certain files in the root file system (see requires:). Sometimes that can not work as expected, though, because the file must exist when your app starts, and some files, like /etc/resolv.conf may get created later, or deleted and re-created as things happen at run time. Another option is to build a small, simple, unsandboxed app that does the file system access and exports an application specific API for use by your main application code, which remains sandboxed. I hope this helps. –Jen

Le_fs_* seems broken

mangOH Red

jyijyi September 25, 2020, 12:28am 6

Other user does not find problem, you can have a look here:

Topic		Replies	Views
Write value in mangOH /sys files mangOH Yellow	5	817	June 26, 2020
Send stuff from mangOH app to /dev/ttyUSBx Uncategorized	2	1289	June 9, 2016
Stdlib in legato project mangOH Green	1	574	October 25, 2018
Cannot create file on SD card from Sandboxed App mangOH Red	11	1931	August 8, 2018
How do I get access the SD card in sandboxed application? mangOH Green	11	1710	August 8, 2018

Le_fs_* seems broken

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