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Simplifying Authenticated Cloud Connectivity for Any Device.
How Wi-Fi and Cellular connectivity modules with ExpressLink can help create secure cloud connected devices. See the blog post.
Designing an energy efficient and cloud-connected IoT solution with CoAP.
A client/server, request/response, UDP-based protocol for efficiency and cloud compatibility. See the blog post.
Introducing FreeRTOS Kernel version 11.0.0:
A Major Release with Symmetric Multiprocessing (SMP) Support. See the blog post.
FreeRTOS Roadmap and Code Contribution process.
The FreeRTOS roadmap and code contribution process are now published here and on GitHub. See the blog post.
OPC-UA over TSN with FreeRTOS.
A development project to give applications consistent access to hardware TSN capabilities. See the blog post.

stdioGET_ERRNO()

[FreeRTOS-Plus-FAT Standard API Reference]

ff_stdio.h 
static portINLINE int stdioGET_ERRNO( void );
  File related functions in the standard C library often return 0 for pass, and -1 for fail. If -1 is returned then the reason for the failure is stored in a variable called errno, which must be inspected separately. FreeRTOS-Plus-FAT's standard stdio style interface maintains an errno variable for each RTOS task. static portINLINE() returns the errno value for the calling task. Notes:
  • The file system's C library style API uses the same errno values as used by the stanard C library. These are documented on a separate page.
  • The file system's native API has a more sophisticated error code system, and returns error codes directly from its API functions.
Example usage: 


void vAFunction( FF_FILE *pxFile, long lOffset, int iWhence )

{

int iReturned;



    /* Attempt to seek a file using the parameters passed into this function. */

    iReturned = ff_fseek( pxFile, lOffset, iWhence );



    if( iReturned == 0 )

    {

        /* The call to ff_fseek() passed. */

    }

    else

    {

        /* The call to ff_fseek() failed. Obtain the errno to see why. */

        iReturned = stdioGET_ERRNO();



        if( iReturned == pdFREERTOS_ERRNO_ESPIPE )

        {

            /* The seep position was illegal - outside of the file's space. */

        }

        else if( iReturned == pdFREERTOS_ERRNO_EINVAL )

        {

            /* The value of iWhence was not legal. */

        }

    }

}




Example use of the stdioGET_ERRNO() API function
 
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