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>Device Major and Minor Numbers</TITLE
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>7. Device Major and Minor Numbers</H1
><P
>The only important thing with a device file are its major
and minor device numbers, which are shown instead of the file
size:</P
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>&#13; $ ls -l /dev/hda
brw-rw---- 1 root disk 8, 0 mars 9 07:56 /dev/sda
</PRE
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>Shows permissions (
<FONT
COLOR="RED"
>brw-rw----</FONT
>), owner (root), group (disk), major
device number (8), minor device number (0), date (mars 9 -
french, no year), hour (07:56) and device name (guess
:-).</P
><P
>When accessing a device file, the major number selects
which device driver is being called to perform the input/output
operation. This call is being done with the minor number as a
parameter and it is entirely up to the driver how the minor
number is being interpreted. The driver documentation usually
describes how the driver uses minor numbers.</P
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