User Guide

Ampex 1308911-02 5-39

libdd2 API Functions dst_getpos

} dst_position_st;

Before calling dst_getpos(), initialize the type member of the *pos structure with the

deﬁnition of the position speciﬁcation you want the drive to return. The other members need not

be initialized.

RETURN VALUES

The return value is DST_SUCCESS (0) or DST_FAILURE (-1). See “DST API Overview” on

page 5-1 for information on

errno failure messages and associated DST result codes.

1. For end of ﬁle (EOF) or end of data (EOD), dst_getpos() succeeds and returns the actual

logical position. It does not return -1 to indicate EOF or EOD. Use dst_status() to determine

if the tape is at EOF or EOD.

2. If no tape is installed, dst_getpos() returns -1 with

errno set to EIO (5) and the DST

result code set to

DstCodeNoTapeInstalled.

3. If the tape is installed but the Ready/Not Ready button on the front panel is Not Ready,

dst_getpos() returns -1 with

errno set to EIO (5) and the DST result code set to

DstCodeNoEstablishedPos.

4. If the tape position cannot be determined, dst_getpos() returns -1 with

errno set to EIO

(5) and the DST result code set to DstCodeGetPosError.

5. dst_getpos() returns

EINVAL (22) if DST_FSN_VAIID, DST_DBN_VALID, and

DST_TIMECODE_VALID are set.