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WHAT'S NEW
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.

f_filelength()

[FreeRTOS Embedded File System API]

header_file.h 
long f_filelength( const char * pcFileName );

Returns the length of a file in the FAT file system.

Parameters:

pcFileName   The name of the file (with or without a path) being queried. The name is specified as a standard null terminated C string.

Returns:
0   Either:
  • The file does not exist.
  • F_FS_THREAD_AWARE is set to 1 and a file system lock could not be obtained before F_MAX_LOCK_WAIT_TICKS elapsed.

Any other value   The length of the file in bytes.

Example usage: 



long lReadFile( char *pcFileName, char *pcBuffer, long lBufferSize )

{

F_FILE *pxFile;

long lFileSize = 0;



    pxFile = f_open( pcFileName, "r" );



    /* Check the file was opened. */

    if( pxFile != NULL )

    {

        /* Obtain the length of the file. */

        lFileSize = f_filelength( pcFileName );



        /* If the contents of the file will fit into the buffer. */

        if( lFileSize <= lBufferSize )

        {

            /* Read the file into the buffer. */

            f_read( pcBuffer, lFileSize, 1, pxFile );

            f_close( pxFile );

        }

    }



    return lFileSize;

}




Example use of the f_filelength() API function
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