The pf_open function opens an existing file.
FRESULT pf_open ( const char* FileName /* Pointer to the file neme */ );
The file must be opend prior to use pf_read and pf_lseek function. The open file is valid until next open.
void main (void)
{
FATFS fs; // Work area (file system object) for the volume
BYTE buff[16]; // File read buffer
UINT br; // File read count
FRESULT res; // Petit FatFs function common result code
// Mount the volume
pf_mount(&fs);
if (res) die(res);
// Open a file
res = pf_open("srcfile.dat");
if (res) die(res);
// Read data to the memory
res = pf_read(buff, 16, &br); // Read data to the buff[]
if (res) die(res); // Check error
if (br != 16) die(255); // Check EOF
....
// Forward data to the outgoing stream
do
res = pf_read(0, 512, &br); // Send data to the stream
while (res || br != 512); // Break on error or eof
....
// Unregister the work area before discard it
f_mount(NULL);
}
Always available.