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for the specified file descriptor.
This is the byte offset of the next byte to be read or written.
It takes no additional argument:
<pre>    position = ioctl (fd, FIOWHERE, 0);
</pre>

<dt>
<b>FIOFLUSH</b>
<dd>

Writes all modified file descriptor buffers to the physical device.
<pre>    status = ioctl (fd, FIOFLUSH, 0);
</pre>

<dt>
<b>FIOSYNC</b>
<dd>

Performs the same function as FIOFLUSH.
<p>

<dt>
<b>FIONREAD</b>
<dd>

Copies to <i>unreadCount</i> the number of bytes from the current file position
to the end of the device:
<pre>    status = ioctl (fd, FIONREAD, &amp;unreadCount);
</pre>
</dl>

<p>

</blockquote><h4>INCLUDE FILES</h4><blockquote><p>
<b>rawFsLib.h</b>
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./rawFsLib.html#top">rawFsLib</a></b>, <b><a href="./ioLib.html#top">ioLib</a></b>, <b><a href="./iosLib.html#top">iosLib</a></b>, <b><a href="./dosFsLib.html#top">dosFsLib</a></b>, <b><a href="./rt11FsLib.html#top">rt11FsLib</a></b>, <b><a href="./ramDrv.html#top">ramDrv</a></b>,  
<i>VxWorks Programmer's Guide: I/O System, Local File Systems</i>

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

</blockquote><h1><i>rawFsDevInit</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>rawFsDevInit</i>(&nbsp;)</strong> - associate a block device with raw volume functions</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>RAW_VOL_DESC *rawFsDevInit
    (
    char *    volName, /* volume name */
    BLK_DEV * pBlkDev  /* pointer to block device info */
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine takes a block device created by a device driver and
defines it as a raw 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 rawFsLib.
<p>
This routine associates <i>volName</i> with a device and installs it in
the VxWorks I/O System's device table.  The driver number used when
the device is added to the table is that which was assigned to the
raw library during <b><i><a href="./rawFsLib.html#rawFsInit">rawFsInit</a></i>(&nbsp;)</b>.  (The driver number is kept in
the global variable <b>rawFsDrvNum</b>.)
<p>
The <b>BLK_DEV</b> structure specified by <i>pBlkDev</i> contains configuration
data describing the device and the addresses of five routines which
will be called to read blocks, write blocks, reset the device, check
device status, and perform other control functions (<b><i><a href="./ioLib.html#ioctl">ioctl</a></i>(&nbsp;)</b>).  These routines
will not be called until they are required by subsequent I/O operations.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
A pointer to the volume descriptor (<b>RAW_VOL_DESC</b>),
or NULL if there is an error.
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./rawFsLib.html#top">rawFsLib</a></b>

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

</blockquote><h1><i>rawFsInit</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>rawFsInit</i>(&nbsp;)</strong> - prepare to use the raw volume library</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS rawFsInit
    (
    int maxFiles /* max no. of simultaneously open files */
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine initializes the raw volume library.  It must be called exactly
once, before any other routine in the library.  The argument specifies the
number of file descriptors that may be open at once.  This routine allocates
and sets up the necessary memory structures and initializes semaphores.
<p>
This routine also installs raw volume library routines in the VxWorks I/O
system driver table.  The driver number assigned to <b><a href="./rawFsLib.html#top">rawFsLib</a></b> is placed in
the global variable <b>rawFsDrvNum</b>.  This number will later be associated
with system file descriptors opened to rawFs devices.
<p>
This initialization is enabled when the configuration macro <b>INCLUDE_RAWFS</b> 
is defined; <b><i><a href="./rawFsLib.html#rawFsInit">rawFsInit</a></i>(&nbsp;)</b> is then called from the root task, <b><i><a href="./usrConfig.html#usrRoot">usrRoot</a></i>(&nbsp;)</b>,
in <b>usrConfig.c</b>.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK or ERROR.
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./rawFsLib.html#top">rawFsLib</a></b>

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

</blockquote><h1><i>rawFsModeChange</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>rawFsModeChange</i>(&nbsp;)</strong> - modify the mode of a raw device volume</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>void rawFsModeChange
    (
    RAW_VOL_DESC * vdptr,  /* pointer to volume descriptor */
    int            newMode /* O_RDONLY/O_WRONLY/O_RDWR (both) */
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine sets the device's mode to <i>newMode</i> by setting the mode field in
the <b>BLK_DEV</b> structure.  This routine should be called whenever the read
and write capabilities are determined, usually after a ready change.
<p>
The driver's device initialization routine should initially set the mode
to <b>O_RDWR</b> (i.e., both <b>O_RDONLY</b> and <b>O_WRONLY</b>).
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
N/A
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./rawFsLib.html#top">rawFsLib</a></b>, <b><i><a href="./rawFsLib.html#rawFsReadyChange">rawFsReadyChange</a></i>(&nbsp;)</b>

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

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

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>void rawFsReadyChange
    (
    RAW_VOL_DESC * vdptr /* pointer to volume descriptor */
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine sets the volume descriptor state to <b>RAW_VD_READY_CHANGED</b>.
It should be called whenever a driver senses that a device has come on-line
or gone off-line, (e.g., a disk has been inserted or removed).
<p>
After this routine has been called, the next attempt to use the volume
will result in an attempted remount.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
N/A
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./rawFsLib.html#top">rawFsLib</a></b>

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

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

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS rawFsVolUnmount
    (
    RAW_VOL_DESC * vdptr /* 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 disks.
All buffered data for the volume is written to the device (if possible),
any open file descriptors are marked as obsolete, and the volume is
marked as not mounted.
<p>
Because this routine will flush data from memory to the physical
device, it should not be used in situations where the disk-change is
not recognized until after a new disk has been inserted.  In these
circumstances, use the ready-change mechanism.  (See the manual entry for 
<b><i><a href="./rawFsLib.html#rawFsReadyChange">rawFsReadyChange</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>SEE ALSO</h4><blockquote><p>
<b><a href="./rawFsLib.html#top">rawFsLib</a></b>, <b><i><a href="./rawFsLib.html#rawFsReadyChange">rawFsReadyChange</a></i>(&nbsp;)</b>

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