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[FreeRTOS Embedded File System API]

long f_filelength( const char * pcFileName );

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


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

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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