This will return the position of the FILE data pointer. The function can be used to determine the size of the file in conjunction with fsFileSeek (with offset set to -1). All data is addressed as 8 bit, and after each successful read or write operation, the file data pointer is automatically incremented.
Input:
fd : FILE
FILE descriptor for the file retrieved from fsFileOpen or fsFileCreate.
Returns: DINT
Position of file pointer.
Declaration:
FUNCTION fsFilePosition : DINT;
VAR_INPUT
fd : FILE;
END_VAR;
Example:
IF fsFileExists(name := "\gpslog.dat") THEN
fdGpslog := fsFileOpen(name := "\gpslog.dat");
IF fsFileStatus(fd := fdGpslog) = 0 THEN
IF fsFilePosition(fd := fdGpslog) > 0 THEN
rc := fsFileSeek(fd := fsGpslog, offset := 0);
IF rc = 0 THEN
REPEAT
len1 := fsFileRead(fd := fdGpslog, buffer := ADDR(linsec), length := SIZEOF(linsec));
len2 := fsFileRead(fd := fdGpslog, buffer := ADDR(lat), length := SIZEOF(lat));
len3 := fsFileRead(fd := fdGpslog, buffer := ADDR(lon), length := SIZEOF(lon));
IF len1 = SIZEOF(linsec) AND len2 = SIZEOF(lat) AND len3 = SIZEOF(lon) THEN
...
END_IF;
UNTIL len1 <> SIZEOF(linsec) OR len2 <> SIZEOF(lat) OR len3 <> SIZEOF(lon)
END_REPEAT;
ELSE
END_IF;
ELSE
END_IF;
fsFileClose(fd := fdGpslog);
ELSE
END_IF;
ELSE
END_IF;
...
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