User Guide

5-66 Ampex 1308911-02
Model No.
Running Head
dst_weof libdd2 API Functions
5.22 dst_weof
NAME
dst_weof() - write filemark(s) to tape
SYNOPSIS
#include <dd2.h>
int dst_weof(int fd, int count);
DESCRIPTION
dst_weof() writes the specified number of filemarks at the current position unless zero
filemarks are specified. In that case, the tape driver buffer is flushed to tape without writing
any filemarks.
Writing a filemark invalidates any data in the partition that was written previously to locations
beyond the filemark. This means you can "quick erase" a partition by positioning to the
Beginning of Partition (BOP), then writing a single filemark. No data is erased, but all data
beyond the filemark is invalidated and the partition is ready for use as though it were empty.
dst_weof() is available to all users.
Note: This data cannot be recovered.
PARAMETERS
fd The file descriptor returned by the open call.
count Indicates the number of filemarks to write to tape. Specifying a value of
zero for count flushes the tape driver data buffer to tape without writing
any filemarks. count must be a positive interger between 0 and 0xffffff.
USAGE
1. When the DST_NO_FLUSH interface parameter is set, all filemarks are written as buffered
filemarks; i.e., the tape drive buffer does not flush to tape unless count is set to zero
(thereby specifying an explicit buffer flush).
2. When th
e DST_NO_FLUSH interface parameter is not set, all filemarks are written as
unbuffered filemarks; i.e., all data and filemarks in the tape drive buffer flush to tape.
3. dst_weof() fails if the current position is undefined.