Ssarazin at 00:19, 5 October 2017

2017-10-05T00:19:46Z

← Older revision		Revision as of 00:19, 5 October 2017
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	Video from the lecture given on September 19, 2017 [http://homeostasis.scs.carleton.ca/~soma/os-2017f/lectures/comp3000-2017f-lec04-19Sep2017.mp4 is now available].		Video from the lecture given on September 19, 2017 [http://homeostasis.scs.carleton.ca/~soma/os-2017f/lectures/comp3000-2017f-lec04-19Sep2017.mp4 is now available].

			==Notes==
			- The textbook
			- Is just for reference as supporting material. The class lectures will not follow the text.

			- Some concepts from the tutorial
			- Running an ltrace on a statically compiled program prints an error. The error just explains that the file was not dynamically compiled "couldn't find .dynsym"
			- What is obj code?
			- machine code. It is important to have a good mental picture of what is happening. Notice that addresses are unique for each process.
			- The point is that the system is not clean, it is complicated and not well understood.

			- How to build a Linux machine using virtualbox and an iso image (concepts)
			- iso: international organization for standardization for optical disk media
			- it's a cd or dvd
			- The VM uses a dynamically allocated hard drive. It is a file that has a filesystem and it grows and shrinks as needed.
			- Hard drive partition: Creates memory segments on the disk that is used to store different types of data.
			- Memory swapping: The processor uses hard disk space when it runs out of RAM.

			- Things about linux
			- '''Why is the kernel split?'''
			- So the various hardware modules can be added to the system when the hardware is installed
			- We can see the modules using ls mod or cd /sys/proc
			- Environment Variables
			- TERM or USER for example. They are capitalized by convention. The significance is that these variables belong to a process (like a shell).
			- Child processes inherit the environment variables from the parent; envp[] stores the values of these variables.
			- Things that can be done in a shell
			- We can run programming commands directly in the shell
			- things like loops and conditionals
			- $ defines a variable
			- echo is the shell's version of printf
			- ssh
			- used to access remote machines using a secure shell
			- The ssh uses a file that stores authorized keys. If a user has a key for the remote terminal then they do not require a password.
			- certificates
			- used by websites to maintain security
			- A secure website encrypts the data so it can't be viewed by hackers.

Soma: /* Video */

2017-09-19T20:52:36Z

Video

← Older revision		Revision as of 20:52, 19 September 2017
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	==Video==		==Video==

	Video from the lecture given on September 14, 2017 [http://homeostasis.scs.carleton.ca/~soma/os-2017f/lectures/comp3000-2017f-lec04-19Sep2017.mp4 is now available].		Video from the lecture given on September 19, 2017 [http://homeostasis.scs.carleton.ca/~soma/os-2017f/lectures/comp3000-2017f-lec04-19Sep2017.mp4 is now available].

Soma: Created page with "==Video== Video from the lecture given on September 14, 2017 [http://homeostasis.scs.carleton.ca/~soma/os-2017f/lectures/comp3000-2017f-lec04-19Sep2017.mp4 is now available]."

2017-09-19T20:52:23Z

Created page with "==Video== Video from the lecture given on September 14, 2017 [http://homeostasis.scs.carleton.ca/~soma/os-2017f/lectures/comp3000-2017f-lec04-19Sep2017.mp4 is now available]."

New page

==Video==

Video from the lecture given on September 14, 2017 [http://homeostasis.scs.carleton.ca/~soma/os-2017f/lectures/comp3000-2017f-lec04-19Sep2017.mp4 is now available].

Operating Systems 2017F Lecture 4 - Revision history

Ssarazin at 00:19, 5 October 2017

Soma: /* Video */

Soma: Created page with "==Video== Video from the lecture given on September 14, 2017 [http://homeostasis.scs.carleton.ca/~soma/os-2017f/lectures/comp3000-2017f-lec04-19Sep2017.mp4 is now available]."