Unix/Lunux MCQ Quiz Hub

1. The directories of /sys directory
are created at system startup when the subsystems register themselves with kobject core
are created when any device is connects with the system
are created at the time of kernel compilation
none of the mentioned

2. The directory /sys/block contains
sub-directories for each block device
symbolic link for each block device only
device file for each block device only
none of the mentioned

3. In sysfs, each represented bus type has two directories named as
attributes and kobjects
devices and drivers
devices and kobjects
none of the mentioned

4. A device class describes the ____ type of device.
physical
stuctural
functional
none of the mentioned

5. Which one of the following directory contains every physical device that has been discovered by the bus types registered with the kernel?
/sys/devices
/sys/bus/devices
/devices
none of the mentioned

6. Which type of devices are peripheral devices?
platform devices
system devices
both system and platform devices
none of the mentioned

7. Which one of the following is not a system device?
CPU
APIC
Timer
None of the mentioned

8. Which one of the following is not a platform specific code?
x86 BIOS
EFI on ia64
both x86 BIOS and EFI on ia64
none of the mentioned

9. In device driver model bus_type object contains the
name of the bus type
name of the bus type
set of kobjects of the devices
all of the mentioned

10. The file fs/sysfs/sysfs.h contains the
internal header files for sysfs
function definitions will not shared locally among the sysfs source
all of the mentioned
none of the mentioned

11. Sysfs is initialised in ______ file via sysfs_init function.
fs/sysfs/mount.c
sysfs/mount.c
fs/mount.c
none of the mentioned

12. Kernel objects are exported as _____ via sysfs.
regular files
symbolic links
directories
none of the mentioned

13. Sysfs internally stores the pointer to the ____ that implements the directory in the file system.
kobjects
kstructures
kinodes
none of the mentioned

14. Attributes can be exported for objects in the form of _______ in the file system.
regular files
directories
symbolic links
none of the mentioned

15. In sysfs every subsystem has
a shared attribute structure
its own attribute structure
a shared & own attribute structure
none of the mentioned

16. sysfs is based on
 rootfs
ramfs
 initramfs
none of the mentioned

17. Which one of the following is a notification to user space from the kernel that something has changed in the system’s configuration?
hotplug event
module event
attach event
none of the mentioned

18. In the device driver model the device_driver object contains the
name of the device driver
embedded kobjects
method for probing a device
all of the mentioned

19. A ____ is a higher level view of a device that abstracts out low level implementation details/
inode
class
major number
minor number

20. When a device is removed from the system
files and directories of that device in the sysfs are removed automatically
all the files of sysfs are preserved until the system turn offs
it does not create any change in the sysfs
none of the mentioned

21. Relationship between components of device driver models are expressed in the sysfs as
a directory
a regular file
symbolic links between files and directories
none of the mentioned

22. What is the main role of the regular files in the sysfs?
regular files represent the attributes of devices and drivers
regular files represent the kernel objects
regular files represent the kernel sets
none of the mentioned

23. The core data structure of device driver model is
kobject
kfile
kmodule
none of the mentioned

24. The kset contains
pointer to subsystem descriptor
pointer to the kobject type descriptor of the kset
head of the kobjects included in the kset
all of the mentioned

25. Which one of the following is a read-write semaphore in linux that protects all ksets and kobjects included in the filesystem?
rwsem
rwsemaphore
rws
none of the mentioned

26. Each device in the device driver model is represented by a _____ object.
driver
device
node
none of the mentioned

27. Each driver in the device driver model is described by a ______ object.
dev_d
device_d
dev_driver
device_driver

28. The channel between the processor and devices is called?
bus
driver
class
none of the mentioned

29. In which directory every kernel module of the system is represented?
/sys/kernel
 /sys/module
/sys/kernel/module
none of the mentioned

30. In sysfs the device drivers of same _____ are expected to provide same functionalities to the user mode application.
class
kobjects
ksets
none of the mentioned

31. Which one of the following is not true?
kobjects are included in a hierarchic organisation
kobjects can have a parent
kobjects can be included in a kset
none of the mentioned

32. In sysfs.h which one of the following structure represents the directory entries?
struct sysfs_dirent
struct sysfs_dir
struct sysfs
none of the mentioned

33. The name pointer of the attribute data structure represents the _____ in sysfs.
directory
file
symbolic link
none of the mentioned

34. To read/write attribute, which one of the following method is required?
show
store
both show and store
none of the mentioned

35. Which one of the following is not contained in the kobject data structure?
pointer to the kobject type descriptor
pointer to the containing kset
pointer to the parent kobject
none of the mentioned

36. The kobjects can be organized in a hierarchical tree by means of
ksets
kref
kref
none of the mentioned

37. Which one of the following is a element of a kset data structure?
pointer to the subsystem descriptor
pointer to the kobject type descriptor of the kset
pointer to the subsystem descriptor & kobject type descriptor of the kset
none of the mentioned

38. Which one of the following function is used to add the kobject to sysfs?
kobject_add()
kobject_register()
kobject_init()
all of the mentioned

39. Which one of the following function is used to create a new attribute?
sysfs_create_file()
sysfs_attribute
both sysfs_create_file() and sysfs_attribute
none of the mentioned

40. Sysfs attribute should export ____ value per file.
one
two
three
four

41. The major number identifies the _____ associated with the device.
driver
protocol
port
none of the mentioned

42. The minor number range should be
 0 to 15
0 to 63
0 to 255
none of the mentioned

43. Which one of the following is not true?
dynamic allocation of major numbers is not possible
major number can not be shared among drivers
dynamic allocation of major numbers is not possible & also major number can not be shared among drivers
none of the mentioned

44. In linux kernel 2.4, we can have
256 character drivers only
256 block drivers only
256 character drivers and 256 block drivers at the same time
none of the mentioned

45. In we use a driver for N number of files, then we have to create ____ device files.
N
1
N-1
None of the mentioned

46. If we use a driver for various device files, then
minor number will be different for every device file
minor number will be same for every device file
minor number can not be allocated for any device file
none of the mentioned

47. The connection between the device file and device driver is based on the
name of device file
number of device file
name & number of device file
none of the mentioned

48.  In linux kernel 2.1, the minor numbers were used to
represnt the sub-functionalitites of the driver
identify the driver
represent the device files
none of the mentioned

49. The kernel identifies the driver with its
module
major number
device file
none of the mentioned

50. In linux, a device driver can work without the
major number
minor number
device file name
none of the mentioned