Operating Systems 2017F: Assignment 3 - Revision history

Soma at 21:49, 30 November 2017

2017-11-30T21:49:46Z

← Older revision		Revision as of 21:49, 30 November 2017
Line 19:		Line 19:
	# [2] What line(s) in newgetpid.c sets the name of the device file (i.e. making it /dev/newgetpid rather than /dev/ones)? How did you verify that your answer was correct?		# [2] What line(s) in newgetpid.c sets the name of the device file (i.e. making it /dev/newgetpid rather than /dev/ones)? How did you verify that your answer was correct?
	# [2] What changes need to be made to newgetpid.c to allow it to respond to write requests? Hint: How does newgetpid.c respond to read requests?		# [2] What changes need to be made to newgetpid.c to allow it to respond to write requests? Hint: How does newgetpid.c respond to read requests?

			==Solutions==

			[http://homeostasis.scs.carleton.ca/~soma/os-2017f/code/lec21/assign3-sol.txt assign3-sol.txt]

Soma at 02:43, 16 November 2017

2017-11-16T02:43:58Z

← Older revision		Revision as of 02:43, 16 November 2017
Line 1:		Line 1:
	~~'''This assignment is not yet finalized.'''~~		Please submit the answers to the following questions via CULearn by 11:55 PM on Sunday, November 26, 2017. There are 20 points in 11 questions.

	Please submit the answers to the following questions via CULearn by 11:55 PM on ~~Thursday~~, November 20, 2017. There are 20 points in 11 questions.

	Submit your answers as a single text file named "<username>-comp3000-assign3.txt" (where username is your MyCarletonOne username). The first four lines of this file should be "COMP 3000 Assignment 3", your name, student number, and the date of submission. You may wish to format your answers in Markdown to improve their appearance.		Submit your answers as a single text file named "<username>-comp3000-assign3.txt" (where username is your MyCarletonOne username). The first four lines of this file should be "COMP 3000 Assignment 3", your name, student number, and the date of submission. You may wish to format your answers in Markdown to improve their appearance.

Soma: /* Questions */

2017-11-15T20:02:32Z

Questions

← Older revision		Revision as of 20:02, 15 November 2017
Line 10:		Line 10:

	==Questions==		==Questions==
	# [1] If you erase the first few blocks of a filesystem, it will become unmountable; however, fsck will generally be able to ~~fix~~ the filesystem. What allows fsck to do the repair?		# [1] If you erase the first few blocks of a filesystem, it will become unmountable; however, fsck will generally be able to recover the filesystem. What extra information stored in the filesystem allows fsck to do the repair?
	# [1] Sometimes the kernel will refuse to unmount a filesystem (when the requesting user has sufficient privileges). What is one important reason why this happens?		# [1] Sometimes the kernel will refuse to unmount a filesystem (when the requesting user has sufficient privileges). What is one important reason why this happens?
	# [2] Why can't you use printf() in Linux kernel modules, but you can use similar C library functions such as snprintf()? More generally, why is only some some of the standard C library available to kernel code?		# [2] Why can't you use printf() in Linux kernel modules, but you can use similar C library functions such as snprintf()? More generally, why is only some some of the standard C library available to kernel code?

Soma at 16:28, 15 November 2017

2017-11-15T16:28:52Z

← Older revision		Revision as of 16:28, 15 November 2017
Line 1:		Line 1:
	'''This assignment is not yet finalized.'''		'''This assignment is not yet finalized.'''

	Please submit the answers to the following questions via CULearn by 11:55 PM on Thursday, November 20, 2017. There are ?? points in ?? questions.		Please submit the answers to the following questions via CULearn by 11:55 PM on Thursday, November 20, 2017. There are 20 points in 11 questions.

	Submit your answers as a single text file named "<username>-comp3000-assign3.txt" (where username is your MyCarletonOne username). The first four lines of this file should be "COMP 3000 Assignment 3", your name, student number, and the date of submission. You may wish to format your answers in Markdown to improve their appearance.		Submit your answers as a single text file named "<username>-comp3000-assign3.txt" (where username is your MyCarletonOne username). The first four lines of this file should be "COMP 3000 Assignment 3", your name, student number, and the date of submission. You may wish to format your answers in Markdown to improve their appearance.

Soma: /* Questions */

2017-11-15T16:27:23Z

Questions

← Older revision		Revision as of 16:27, 15 November 2017
Line 12:		Line 12:
	# [1] If you erase the first few blocks of a filesystem, it will become unmountable; however, fsck will generally be able to fix the filesystem. What allows fsck to do the repair?		# [1] If you erase the first few blocks of a filesystem, it will become unmountable; however, fsck will generally be able to fix the filesystem. What allows fsck to do the repair?
	# [1] Sometimes the kernel will refuse to unmount a filesystem (when the requesting user has sufficient privileges). What is one important reason why this happens?		# [1] Sometimes the kernel will refuse to unmount a filesystem (when the requesting user has sufficient privileges). What is one important reason why this happens?
			# [2] Why can't you use printf() in Linux kernel modules, but you can use similar C library functions such as snprintf()? More generally, why is only some some of the standard C library available to kernel code?
			# [2] What is a process's effective uid (euid)? Why is the euid not always equal to its uid?
	# [2] When you load a kernel module, are you creating a new process? Why or why not?		# [2] When you load a kernel module, are you creating a new process? Why or why not?
	# [2] Is a running Linux system that is generating multiple "Oops" messages at risk of doing something bad, like corrupting data or crashing? Explain.		# [2] Is a running Linux system that is generating multiple "Oops" messages at risk of doing something bad, like corrupting data or crashing? Explain.
			# [2] Why does newgetpid.c use put_user() in newgetpid_read(), rather than just writing directly to buf? Explain briefly.
	# [2] How can the logical size of a filesystem be larger than the physical size? How can the logical size be smaller than the physical size?		# [2] How can the logical size of a filesystem be larger than the physical size? How can the logical size be smaller than the physical size?
	# [2] What type is "current" normally in Linux source code? What does "current" refer to?		# [2] What type is "current" normally in Linux source code? What does "current" refer to?
	# [2] What line(s) in newgetpid.c sets the name of the device file (i.e. making it /dev/newgetpid rather than /dev/ones)? How did you verify that your answer was correct?		# [2] What line(s) in newgetpid.c sets the name of the device file (i.e. making it /dev/newgetpid rather than /dev/ones)? How did you verify that your answer was correct?
	# [2] What changes need to be made to newgetpid.c to allow it to respond to write requests? Hint: How does newgetpid.c respond to read requests?		# [2] What changes need to be made to newgetpid.c to allow it to respond to write requests? Hint: How does newgetpid.c respond to read requests?

Soma: /* Questions */

2017-11-15T16:20:13Z

Questions

← Older revision		Revision as of 16:20, 15 November 2017
Line 12:		Line 12:
	# [1] If you erase the first few blocks of a filesystem, it will become unmountable; however, fsck will generally be able to fix the filesystem. What allows fsck to do the repair?		# [1] If you erase the first few blocks of a filesystem, it will become unmountable; however, fsck will generally be able to fix the filesystem. What allows fsck to do the repair?
	# [1] Sometimes the kernel will refuse to unmount a filesystem (when the requesting user has sufficient privileges). What is one important reason why this happens?		# [1] Sometimes the kernel will refuse to unmount a filesystem (when the requesting user has sufficient privileges). What is one important reason why this happens?
			# [2] When you load a kernel module, are you creating a new process? Why or why not?
	# [2] Is a running Linux system that is generating multiple "Oops" messages at risk of doing something bad, like corrupting data or crashing? Explain.		# [2] Is a running Linux system that is generating multiple "Oops" messages at risk of doing something bad, like corrupting data or crashing? Explain.
	# [2] How can the logical size of a filesystem be larger than the physical size? How can the logical size be smaller than the physical size?		# [2] How can the logical size of a filesystem be larger than the physical size? How can the logical size be smaller than the physical size?

Soma: /* Questions */

2017-11-15T16:18:03Z

Questions

← Older revision		Revision as of 16:18, 15 November 2017
Line 11:		Line 11:
	==Questions==		==Questions==
	# [1] If you erase the first few blocks of a filesystem, it will become unmountable; however, fsck will generally be able to fix the filesystem. What allows fsck to do the repair?		# [1] If you erase the first few blocks of a filesystem, it will become unmountable; however, fsck will generally be able to fix the filesystem. What allows fsck to do the repair?
			# [1] Sometimes the kernel will refuse to unmount a filesystem (when the requesting user has sufficient privileges). What is one important reason why this happens?
			# [2] Is a running Linux system that is generating multiple "Oops" messages at risk of doing something bad, like corrupting data or crashing? Explain.
	# [2] How can the logical size of a filesystem be larger than the physical size? How can the logical size be smaller than the physical size?		# [2] How can the logical size of a filesystem be larger than the physical size? How can the logical size be smaller than the physical size?
	# [1] ~~Sometimes the kernel will refuse~~ to ~~unmount a filesystem~~ (~~when~~ the ~~requesting user has sufficient privileges~~). ~~What is one important reason why this happens~~?		# [2] What type is "current" normally in Linux source code? What does "current" refer to?
	# [1] ~~Describe one way for a Linux kernel module~~ to ~~generate an "Oops" message~~.		# [2] What line(s) in newgetpid.c sets the name of the device file (i.e. making it /dev/newgetpid rather than /dev/ones)? How did you verify that your answer was correct?
			# [2] What changes need to be made to newgetpid.c to allow it to respond to write requests? Hint: How does newgetpid.c respond to read requests?

Soma: Created page with "'''This assignment is not yet finalized.''' Please submit the answers to the following questions via CULearn by 11:55 PM on Thursday, November 20, 2017. There are ?? points i..."

2017-11-14T17:38:42Z

Created page with "'''This assignment is not yet finalized.''' Please submit the answers to the following questions via CULearn by 11:55 PM on Thursday, November 20, 2017. There are ?? points i..."

New page

'''This assignment is not yet finalized.'''

Please submit the answers to the following questions via CULearn by 11:55 PM on Thursday, November 20, 2017. There are ?? points in ?? questions.

Submit your answers as a single text file named "<username>-comp3000-assign3.txt" (where username is your MyCarletonOne username). The first four lines of this file should be "COMP 3000 Assignment 3", your name, student number, and the date of submission. You may wish to format your answers in Markdown to improve their appearance.

No other formats will be accepted. Submitting in another format will likely result in your assignment not being graded and you receiving no marks for this assignment. In particular do not submit an MS Word or OpenOffice file as your answers document!

Don't forget to include what outside resources you used to complete each of your answers, including other students, man pages, and web resources. You do not need to list help from the instructor, TA, or information found in the textbook.

==Questions==
# [1] If you erase the first few blocks of a filesystem, it will become unmountable; however, fsck will generally be able to fix the filesystem. What allows fsck to do the repair?
# [2] How can the logical size of a filesystem be larger than the physical size? How can the logical size be smaller than the physical size?
# [1] Sometimes the kernel will refuse to unmount a filesystem (when the requesting user has sufficient privileges). What is one important reason why this happens?
# [1] Describe one way for a Linux kernel module to generate an "Oops" message.