User Guide

5-68 Ampex 1308911-02
Model No.
Running Head
dst_weof_ex libdd2 API Functions
5.23 dst_weof_ex
NAME
dst_weof_ex() - write filemarks to tape (extended).
SYNOPSIS
#include <dd2.h>
int dst_weof_ex(int fd, int count, int flush);
DESCRIPTION
dst_weof_ex() 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.
The flush argument specifies whether buffered or unbuffered filemarks should be written.
When the
DST_NO_FLUSH interface parameter bit is set, it overrides the flush argument
unless zero filemarks are to be written, i.e., the program explicitly specifies that the tape drive
buffer be flushed to tape.
dst_weof_ex() is available to all users.
Note: This data cannot be recovered.
PARAMETERS
fd The file descriptor returned by the open call.
count Specifies the number of filemarks to write. Setting count to zero flushes
the drive buffer to tape without writing any filemarks. count must be a
positive interger between 0 and 0xffffff.
flush When count is set to a value greater than zero and the
DST_NO_FLUSH
interface parameter is not set, flush specifies whether buffered or
unbuffered filemarks are written. Set flush to zero for buffered filemarks
or one for unbuffered filemarks.