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35 lines
1.1 KiB
Plaintext
35 lines
1.1 KiB
Plaintext
-> /proc/devices:
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It contains the character and block devices
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with their major number.
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-> Why character devices are called character devices?
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Because the read/write operation done is in size of
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byte.
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-> Why block devices are called block devices?
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Because the read/write operation done is in size of
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block.
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-> To read bytes of a devices
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use:
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hexdump /dev/<device_name>
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to see only few bytes
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Use:
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hexdump /dev/<device_name> | head
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-> To create a new device file
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Use:
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mknod <device-name> <type of device 'c' or 'b'> <major-num> <minor-num>
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-> /dev/*:
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this file basically contains virtual files which act as a
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interface between the device driver in kernel space and
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the user space, which allow the control of the device from
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user space.
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-> The link between the driver and the device file is made over
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the major and minor number of the device file rather than
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name of the device file. So, if I associate a custom made
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device file with driver using same major and minor number.
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I can access the same device using that file. |