DOSINT64 oldpos = FSeek(APTR handle, DOSINT64 pos, int mode);

HWFSEEKMODE_CURRENT:

New seek position is relative to the current position.

HWFSEEKMODE_BEGINNING:

New seek position is relative to the beginning of the file.

HWFSEEKMODE_END:

New seek position is relative to the end of the file.

Note that FSeek() is often called with a 0 zero position and HWFSEEKMODE_CURRENT to query the position of the read/write cursor.

If there was an error, FSeek() has to return -1.

If you set the HWFOPENFLAGS_NOSEEK flag in your FOpen() implementation, your FSeek() implementation only has to support rewinding the file and querying the position of the cursor. In terms of code, this means that FSeek() only has to support the following two operations if HWFOPENFLAGS_NOSEEK is set:

FSeek(fh, 0, HWFSEEKMODE_BEGINNING); // rewind pos = FSeek(fh, 0, HFSEEKMODE_CURRENT); // query cursor position

For any other operation, it has to return -1, i.e. an error has occurred.

This function must be implemented in a thread-safe manner.

handle

file handle returned by FOpen()

pos

destination seek position

mode

seek mode (see above)

oldpos

previous position of file cursor or -1 on error