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<A NAME="PAGENUM-1155"><P>Page 1155</P></A>
<P>For example, the following drive section describes a 1.44M drive:
</P>
<!-- CODE SNIP //-->
<PRE>
drive a:
file="/dev/fd0H1440"
fat_bits=12
tracks=80 heads=2 sectors=18
</PRE>
<!-- END CODE SNIP //-->
<P>The following shorthand geometry descriptions are available:
</P>
<TABLE>
<TR><TD>
1.44M
</TD><TD>
High density, 3 1/2 disk. Equivalent to
fat_bits=12 tracks=80 heads=2 sectors=18.
</TD></TR><TR><TD>
1.2M
</TD><TD>
High density, 5 1/4 disk. Equivalent to
fat_bits=12 tracks=80 heads=2 sectors=15.
</TD></TR><TR><TD>
720K
</TD><TD>
Double density, 3 1/2 disk. Equivalent to
fat_bits=12 tracks=80 heads=2 sectors=9.
</TD></TR><TR><TD>
360K
</TD><TD>
Double density, 5 1/4 disk. Equivalent to
fat_bits=12 tracks=40 heads=2 sectors=9.
</TD></TR></TABLE>
<P>The shorthand format descriptions may be amended. For example,
360K sectors=8 describes a 320K disk and is equivalent
to fat_bits=12 tracks=40 heads=2 sectors=8.
</P>
<P><B>
OPEN FLAGS
</B></P>
<P>Moreover, the following flags are available:
</P>
<TABLE>
<TR><TD>
sync
</TD><TD>
All I/O operations are done synchronously.
</TD></TR><TR><TD>
nodelay
</TD><TD>
The device or file is opened with the
O_NDELAY flag. This is needed on some non-Linux architectures.
</TD></TR><TR><TD>
exclusive
</TD><TD>
The device or file is opened with the
O_EXCL flag. On Linux, this ensures exclusive access
to the floppy drive. On most other architectures and for plain files, it has no effect at all.
</TD></TR></TABLE>
<P><B>
SUPPLYING MULTIPLE DESCRIPTIONS FOR A DRIVE
</B></P>
<P>It is possible to supply multiple descriptions for a drive. In that case, the descriptions are tried in order until one is
found that fits. Descriptions may fail for several reasons:
</P>
<UL>
<LI> The geometry is not appropriate
<LI> There is no disk in the drive
<LI> Other problems
</UL>
<P>Multiple definitions are useful when using physical devices that are only able to support one single disk geometry:
</P>
<!-- CODE SNIP //-->
<PRE>
drive a: file="/dev/fd0H1440" 1.44m
drive a: file="/dev/fd0H720" 720k
</PRE>
<!-- END CODE SNIP //-->
<P>This instructs mtools to use /dev/fd0H1440 for 1.44M (high density) disks and
/dev/fd0H720 for 720K (double density) disks. On Linux, this feature is not really needed because the
/dev/fd0 device is able to handle any geometry.
</P>
<P>You can also use multiple drive descriptions to access both of your physical drives through one drive letter:
</P>
<!-- CODE SNIP //-->
<PRE>
drive z: file="/dev/fd0"
drive z: file="/dev/fd1"
</PRE>
<!-- END CODE SNIP //-->
<P>With this description, mdir z: accesses your first physical drive if it contains a disk. If the first drive doesn't contain a
disk, mtools checks the second drive.
</P>
<P>When using multiple configuration files, drive descriptions in the files parsed last override descriptions for the same drive
in earlier files. In order to avoid this, use the
drive+ or +drive keywords instead of drive. The first adds a description to the
end of the list (will be tried last), and the second adds it to the start of the list.
</P>
<P><B>
CHARACTER TRANSLATION TABLES
</B></P>
<P>If you live in the USA, in Western Europe, or in Australia, you can skip this section.
</P>
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