FILE_POSITION

Syntax where = FILE_POSITION(#channel)
Location DJToolkit 1.16

This function will tell you exactly where you are in the file that has been opened, to a directory device, as #channel, if the result returned is negative it is a QDOS error code. If the file has just been opened, the result will be zero, if the file is at the very end, the result will be the same as calling FILE_LENGTH(#channel) - 1, files start at byte zero remember.

EXAMPLE

1500 DEFine FuNction OPEN_APPEND(f$)
1510   LOCal ch, fp
1515   :
1520   REMark Open a file at the end, ready for additional
1530   REMark data to be appended.
1540   REMark Returns the channel number. (Or error)
1545   :
1550   ch = DJ_OPEN(f$)
1560   IF ch < 0 THEN
1570      PRINT "Error: " & ch & " Opening file: " & f$
1580      RETurn ch
1590   END IF
1595   :
1600   MOVE_POSITION #ch, 6e6
1610   fp = FILE_POSITION(#ch)
1620   IF fp < 0 THEN
1630      PRINT "Error: " & fp & " reading file position on: " & f$
1640      CLOSE #ch
1650      RETurn fp
1660   END IF
1665   :
1670   PRINT "File position set to EOF at: " & fp & " on file: " &f$
1680   RETurn ch
1690 END DEFine

CROSS-REFERENCE

ABS_POSITION, MOVE_POSITION.