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<dt>
MTFSR
<dd>

Forward space over a data block and position the tape head in the gap between
the block just skipped and the next block.
Any buffered data is flushed out to the tape if the tape is in write
mode.
<p>

<dt>
MTBSR
<dd>

Backward space over a data block and position the tape head right before the
block just skipped.
Any buffered data is flushed out to the tape if the tape is in write
mode.
<p>

<dt>
MTREW
<dd>

Rewind the tape to the beginning of the medium.
Any buffered data is flushed out to the tape if the tape is in write
mode.
<p>

<dt>
MTOFFL
<dd>

Rewind and unload the tape.
Any buffered data is flushed out to the tape if the tape is in write
mode.
<p>

<dt>
MTNOP
<dd>

No operation, but check the status of the device, thus setting the appropriate
<b>SEQ_DEV</b> fields.
<p>

<dt>
MTRETEN
<dd>

Retension the tape. This command usually sets tape tension and can be
used in either read or write mode.
Any buffered data is flushed out to tape if the tape is in write
mode.
<p>

<dt>
MTERASE
<dd>

Erase the entire tape and rewind it.
<p>

<dt>
MTEOM
<dd>

Position the tape at the end of the medium and unload the tape.
Any buffered data is flushed out to the tape if the tape is in write
mode.
<p>
 
</dl>

</blockquote><h4>INCLUDE FILES</h4><blockquote><p>
<p>
&nbsp;<b>tapeFsLib.h</b>
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./tapeFsLib.html#top">tapeFsLib</a></b>, <b><a href="./ioLib.html#top">ioLib</a></b>, <b><a href="./iosLib.html#top">iosLib</a></b>,  
<i>VxWorks Programmer's Guide: I/O System, Local File Systems</i>

<hr>
<a name="tapeFsDevInit"></a>
<p align=right>
<a href="rtnIndex.html"><i>Libraries :  Routines</i></a></p>

</blockquote><h1><i>tapeFsDevInit</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>tapeFsDevInit</i>(&nbsp;)</strong> - associate a sequential device with tape volume functions</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>TAPE_VOL_DESC *tapeFsDevInit
    (
    char *        volName,    /* volume name */
    SEQ_DEV *     pSeqDev,    /* pointer to sequential device info */
    TAPE_CONFIG * pTapeConfig /* pointer to tape config info */
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine takes a sequential device created by a device driver and
defines it as a tape file system volume.  As a result, when high-level 
I/O operations, such as <b><i><a href="./ioLib.html#open">open</a></i>(&nbsp;)</b> and <b><i><a href="./ioLib.html#write">write</a></i>(&nbsp;)</b>, are performed on the
device, the calls will be routed through tapeFsLib.
<p>
This routine associates <b>volName</b> with a device and installs it in
the VxWorks I/O system-device table.  The driver number used when
the device is added to the table is that which was assigned to the
tape library during <b><i><a href="./tapeFsLib.html#tapeFsInit">tapeFsInit</a></i>(&nbsp;)</b>.  (The driver number is kept in
the global variable <b>tapeFsDrvNum</b>.)
<p>
The <b>SEQ_DEV</b> structure specified by <b>pSeqDev</b> contains configuration
data describing the device and the addresses of the routines which
are called to read blocks, write blocks, write file marks, reset the 
device, check device status, perform other I/O control functions (<b><i><a href="./ioLib.html#ioctl">ioctl</a></i>(&nbsp;)</b>),
reserve and release devices, load and unload devices, and rewind devices.
These routines are not called until they are required by subsequent I/O
operations.  The <b>TAPE_CONFIG</b> structure is used to define configuration
parameters for the <b>TAPE_VOL_DESC</b>.  The configuration parameters are defined
and described in <b>tapeFsLib.h</b>.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
A pointer to the volume descriptor (<b>TAPE_VOL_DESC</b>),
or NULL if there is an error.
<p>
</blockquote><h4>ERRNO</h4><blockquote><p>
S_tapeFsLib_NO_SEQ_DEV, S_tapeFsLib_ILLEGAL_TAPE_CONFIG_PARM
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./tapeFsLib.html#top">tapeFsLib</a></b>

<hr>
<a name="tapeFsInit"></a>
<p align=right>
<a href="rtnIndex.html"><i>Libraries :  Routines</i></a></p>

</blockquote><h1><i>tapeFsInit</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>tapeFsInit</i>(&nbsp;)</strong> - initialize the tape volume library</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>

STATUS tapeFsInit ()</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine initializes the tape volume library.  It must be called exactly
once, before any other routine in the library. Only one file descriptor
per volume is assumed. 
<p>
This routine also installs tape volume library routines in the VxWorks I/O
system driver table.  The driver number assigned to <b><a href="./tapeFsLib.html#top">tapeFsLib</a></b> is placed in
the global variable <b>tapeFsDrvNum</b>.  This number is later associated
with system file descriptors opened to tapeFs devices.
<p>
To enable this initialization, simply call the routine <b><i><a href="./tapeFsLib.html#tapeFsDevInit">tapeFsDevInit</a></i>(&nbsp;)</b>, which
automatically calls <b><i><a href="./tapeFsLib.html#tapeFsInit">tapeFsInit</a></i>(&nbsp;)</b> in order to initialize the tape file system.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK or ERROR.
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./tapeFsLib.html#top">tapeFsLib</a></b>

<hr>
<a name="tapeFsReadyChange"></a>
<p align=right>
<a href="rtnIndex.html"><i>Libraries :  Routines</i></a></p>

</blockquote><h1><i>tapeFsReadyChange</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>tapeFsReadyChange</i>(&nbsp;)</strong> - notify <b><a href="./tapeFsLib.html#top">tapeFsLib</a></b> of a change in ready status</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS tapeFsReadyChange
    (
    TAPE_VOL_DESC * pTapeVol /* pointer to volume descriptor */
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine sets the volume descriptor state to <b>TAPE_VD_READY_CHANGED</b>.
It should be called whenever a driver senses that a device has come on-line
or gone off-line (for example, that a tape has been inserted or removed).
<p>
After this routine has been called, the next attempt to use the volume
results in an attempted remount.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK if the read change status is set, or ERROR if the file descriptor
is in use.
<p>
</blockquote><h4>ERRNO</h4><blockquote><p>
S_tapeFsLib_FILE_DESCRIPTOR_BUSY
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./tapeFsLib.html#top">tapeFsLib</a></b>

<hr>
<a name="tapeFsVolUnmount"></a>
<p align=right>
<a href="rtnIndex.html"><i>Libraries :  Routines</i></a></p>

</blockquote><h1><i>tapeFsVolUnmount</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>tapeFsVolUnmount</i>(&nbsp;)</strong> - disable a tape device volume</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS tapeFsVolUnmount
    (
    TAPE_VOL_DESC * pTapeVol /* pointer to volume descriptor */
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine is called when I/O operations on a volume are to be
discontinued.  This is commonly done before changing removable tape.
All buffered data for the volume is written to the device (if possible),
any open file descriptors are marked obsolete, and the volume is
marked not mounted.
<p>
Because this routine flushes data from memory to the physical
device, it should not be used in situations where the tape-change is
not recognized until after a new tape has been inserted.  In these
circumstances, use the ready-change mechanism.  (See the manual entry for 
<b><i><a href="./tapeFsLib.html#tapeFsReadyChange">tapeFsReadyChange</a></i>(&nbsp;)</b>.)
<p>
This routine may also be called by issuing an <b><i><a href="./ioLib.html#ioctl">ioctl</a></i>(&nbsp;)</b> call using the
FIOUNMOUNT function code.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK, or ERROR if the routine cannot access the volume.
<p>
</blockquote><h4>ERRNO</h4><blockquote><p>
<p>
S_tapeFsLib_VOLUME_NOT_AVAILABLE,
S_tapeFsLib_FILE_DESCRIPTOR_BUSY,
S_tapeFsLib_SERVICE_NOT_AVAILABLE
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./tapeFsLib.html#top">tapeFsLib</a></b>, <b><i><a href="./tapeFsLib.html#tapeFsReadyChange">tapeFsReadyChange</a></i>(&nbsp;)</b>

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