National Instruments 320682C

Chapter 2 Formatting and I/O Library

then reads the correct number of elements into values. The x modifier causes the comma

separators to be discarded.

Binary File to Integer Array, Assuming a Fixed Number of Elements

int readings[100];

int file_handle, nbytes;

file_handle = OpenFile ("FILE.DAT", 1, 2, 0);

ScanFile (file_handle, "%100i>%100i", readings);

nbytes = NumFmtdBytes ();

CloseFile (file_handle);

Remarks

The ScanFile call reads 100 integers from a binary file and stores them in the integer array

readings. If the ScanFile call is successful, nbytes = 200 (100 integers, 2 bytes per

integer).

Binary File to Real Array, Assuming a Fixed Number of Elements

double waveform[100];

int file_handle, nbytes;

file_handle = OpenFile ("FILE.DAT", 1, 2, 0);

ScanFile (file_handle, "%100f>%100f", waveform);

nbytes = NumFmtdBytes ();

CloseFile (file_handle);

Remarks

The ScanFile call reads 100 real numbers from a binary file and stores them in the real array

waveform. If the ScanFile call is successful, nbytes = 800 (100 integers, 8 bytes per real

number).

Binary File to Real Array, Assuming a Variable Number of Elements

void StoreArray (double x[], int count, char filename[])

{int file_handle;

file_handle = OpenFile (filename, 1, 2, 0);

ScanFile (file_handle, "%*f>%*f", count, count, x);

CloseFile (file_handle);

}