COMP3000 Operating Systems 2023F Tutorials: Tutorial 1 - Revision history

Abdou: /* Tasks/Questions */

2023-09-22T03:55:57Z

Tasks/Questions

← Older revision		Revision as of 03:55, 22 September 2023
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	# What does it mean to have execute permission on a directory?		# What does it mean to have execute permission on a directory?
	# The <code>ls</code> command can be used to get a listing of the files in a directory. What options are passed to <code>ls</code> to see: the permission bits above; all the files within a directory (including hidden files)? How to make a file hidden?		# The <code>ls</code> command can be used to get a listing of the files in a directory. What options are passed to <code>ls</code> to see: the permission bits above; all the files within a directory (including hidden files)? How to make a file hidden?
	# Compile and run [https://people.scs.~~carletgon~~.ca/~abdou/comp3000/f23/tut1/csimpleshell.c <tt>csimpleshell.c</tt>]. <u>How does its functionality compare to that of <code>bash</code></u>? List at least 3 differences.		# Compile and run [https://people.scs.carleton.ca/~abdou/comp3000/f23/tut1/csimpleshell.c <tt>csimpleshell.c</tt>]. <u>How does its functionality compare to that of <code>bash</code></u>? List at least 3 differences.

Abdou: /* Tasks/Questions */

2023-09-22T03:54:19Z

Tasks/Questions

Abdou: /* Compiling & Running Programs */

2023-09-22T03:49:29Z

Compiling & Running Programs

← Older revision		Revision as of 03:49, 22 September 2023
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	./hello		./hello

	Remember you can always change directories using the <code>cd</code command.		Remember you can always change directories using the <code>cd</code> command.

	==Tasks/Questions==		==Tasks/Questions==

Abdou: /* Compiling & Running Programs */

2023-09-22T03:49:16Z

Compiling & Running Programs

← Older revision		Revision as of 03:49, 22 September 2023
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	./hello		./hello

	Remember you can always change directories using the <tt>cd</~~tt>~~ command.		Remember you can always change directories using the <code>cd</code command.

	==Tasks/Questions==		==Tasks/Questions==

Abdou: /* Downloading files using commands */

2023-09-22T03:48:25Z

Downloading files using commands

← Older revision		Revision as of 03:48, 22 September 2023
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	When working with the command line and you need to download a small number of files from a website, you can choose one of the two below:		When working with the command line and you need to download a small number of files from a website, you can choose one of the two below:

	curl -o hello.c [https://people.scs.carleton.ca/~~~lianyingzhao~~/comp3000/~~w23~~/tut1/hello.c https://people.scs.carleton.ca/~~~lianyingzhao~~/comp3000/~~w23~~/tut1/hello.c]		curl -o hello.c [https://people.scs.carleton.ca/~abdou/comp3000/f23/tut1/hello.c https://people.scs.carleton.ca/~abdou/comp3000/f23/tut1/hello.c]
	wget [https://people.scs.carleton.ca/~~~lianyingzhao~~/comp3000/~~w23~~/tut1/hello.c https://people.scs.carleton.ca/~~~lianyingzhao~~/comp3000/~~w23~~/tut1/hello.c]		wget [https://people.scs.carleton.ca/~abdou/comp3000/f23/tut1/hello.c https://people.scs.carleton.ca/~abdou/comp3000/f23/tut1/hello.c]

	Use <code>man curl</code> and <code>man wget</code> to find out more about these commands, if you are interested.		Use <code>man curl</code> and <code>man wget</code> to find out more about these commands, if you are interested.

Abdou: /* Downloading files using commands */

2023-09-22T03:47:43Z

Downloading files using commands

← Older revision		Revision as of 03:47, 22 September 2023
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	Use <code>man curl</code> and <code>man wget</code> to find out more about these commands, if you are interested.		Use <code>man curl</code> and <code>man wget</code> to find out more about these commands, if you are interested.

	In later tutorials, this will be useful as you need source files to do your work, for which the URL will be just a hyperlink on this wiki page ~~or a PDF~~.		In later tutorials, this will be useful as you need source files to do your work, for which the URL will be just a hyperlink on this wiki page.

	===Compiling & Running Programs===		===Compiling & Running Programs===

Abdou: /* Downloading files using commands */

2023-09-22T03:47:28Z

Downloading files using commands

← Older revision		Revision as of 03:47, 22 September 2023
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	===Downloading files using commands===		===Downloading files using commands===
	When working with the command line and you need to download a small number of files from a website ~~(i.e., using the Web/HTTP protocol)~~, you can choose one of the two below ~~(use <tt>man</tt> to find out more if interested)~~:		When working with the command line and you need to download a small number of files from a website, you can choose one of the two below:

	curl -o hello.c [https://people.scs.carleton.ca/~lianyingzhao/comp3000/w23/tut1/hello.c https://people.scs.carleton.ca/~lianyingzhao/comp3000/w23/tut1/hello.c]		curl -o hello.c [https://people.scs.carleton.ca/~lianyingzhao/comp3000/w23/tut1/hello.c https://people.scs.carleton.ca/~lianyingzhao/comp3000/w23/tut1/hello.c]
	wget [https://people.scs.carleton.ca/~lianyingzhao/comp3000/w23/tut1/hello.c https://people.scs.carleton.ca/~lianyingzhao/comp3000/w23/tut1/hello.c]		wget [https://people.scs.carleton.ca/~lianyingzhao/comp3000/w23/tut1/hello.c https://people.scs.carleton.ca/~lianyingzhao/comp3000/w23/tut1/hello.c]

			Use <code>man curl</code> and <code>man wget</code> to find out more about these commands, if you are interested.

	In later tutorials, this will be useful as you need source files to do your work, for which the URL will be just a hyperlink on this wiki page or a PDF.		In later tutorials, this will be useful as you need source files to do your work, for which the URL will be just a hyperlink on this wiki page or a PDF.

Abdou: /* Environment & Shell Variables */

2023-09-22T03:46:09Z

Environment & Shell Variables

← Older revision		Revision as of 03:46, 22 September 2023
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	To delete an environment variable, you can use the command <code>unset</code>. For example:		To delete an environment variable, you can use the command <code>unset</code>. For example:

	unset X.		unset X

	===Downloading files using commands===		===Downloading files using commands===

Abdou: /* Environment & Shell Variables */

2023-09-22T03:45:56Z

Environment & Shell Variables

← Older revision		Revision as of 03:45, 22 September 2023
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	To delete an environment variable, you can use the command <code>unset</code>. For example:		To delete an environment variable, you can use the command <code>unset</code>. For example:

	unset X.		unset X.

	===Downloading files using commands===		===Downloading files using commands===

Abdou: /* Environment & Shell Variables */

2023-09-22T03:45:43Z

Environment & Shell Variables

← Older revision		Revision as of 03:45, 22 September 2023
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	as you now are giving export three arguments, not one.		as you now are giving export three arguments, not one.

	To delete an environment variable, you can <tt>unset X</tt>.		To delete an environment variable, you can use the command <code>unset</code>. For example:

			unset X.

	===Downloading files using commands===		===Downloading files using commands===

← Older revision		Revision as of 03:54, 22 September 2023
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	==Tasks/Questions==		==Tasks/Questions==
	# When you have first logged in to a shell, <u>how</u> (i.e., using what commands?) can you find out information about the environment? Consider the following as examples. Try to find out ~~mutiple~~ ways for each (if you can).		# When you have first logged in to a shell, <u>how</u> (i.e., using what commands?) can you find out information about the environment? Consider the following as examples. Try to find out multiple ways for each (if you can).
	#* The version of your Linux distribution (in our case, Ubuntu) and the version of your Linux kernel.		#* The version of your Linux distribution (in our case, Ubuntu) and the version of your Linux kernel.
	#* RAM (remaining/total), disk space (remaining/total), and CPU.		#* RAM (remaining/total), disk space (remaining/total), and CPU.
	#* The name (binary path) of the current shell.		#* The name (binary path) of the current shell.
	# Using the <tt>man</tt> command, find out what the following commands do: <tt>which</tt>, <tt>pwd</tt>, <tt>who</tt>, <tt>whoami</tt>, <tt>whereis</tt>, and <tt>whatis</tt>.		# Using the <code>man</code> command, find out what the following commands do: <code>which</code>, <code>pwd</code>, <code>who</code>, <code>whoami</code>, <code>whereis</code>, and <code>whatis</code>.
	# Linux commands can be classified as internal (built into the shell) and external (separate program binaries). <u>How can you tell</u> if a specific command (e.g., <tt>cd</tt>) is internal or external?		# Linux commands can be classified as internal (built into the shell) and external (separate program binaries). <u>How can you tell</u> if a specific command (e.g., <code>cd</code>) is internal or external?
	#* For the program you just compiled above, what if you used <tt>hello</tt> to run it instead of <tt>./hello</tt> (and why)?		#* For the program you just compiled above, what if you used <code>hello</code> to run it instead of <code>./hello</code> (and why)?
	#* Figure out where at least three external commands reside on the system.		#* Figure out where at least three external commands reside on the system.
	# Making your own commands: the <tt>PATH</tt> environment variable lists the directories the shell uses to search for external commands. Where can you find documentation on it? How can you add the current directory (whichever directory you are currently in) to PATH? Then, how to make that change permanent? Try to identify multiple ways. You can now revisit the question about "hello" above.		# Making your own commands: the <code>PATH</code> environment variable lists the directories the shell uses to search for external commands. Where can you find documentation on it? How can you add the current directory (whichever directory you are currently in) to PATH? Then, how to make that change permanent? Try to identify multiple ways. You can now revisit the question about "hello" above.
	# Look at the permissions of the program binaries of the external commands you have just found above. Who owns them? What group are they in?		# Look at the permissions of the program binaries of the external commands you have just found above. Who owns them? What group are they in?
	# For those same program binaries, figure out what the permission bits mean by reading the man page of <tt>chmod</tt> (this is the command you could use to change those permission bits).		# For those same program binaries, figure out what the permission bits mean by reading the man page of <code>chmod</code> (this is the command you could use to change those permission bits).
	# What are the owner, group, and permissions of <tt>/etc/passwd</tt> and <tt>/etc/shadow</tt>? What are these files used for (and <u>how did you find this out</u>)?		# What are the owner, group, and permissions of <code>/etc/passwd</code> and <code>/etc/shadow</code>? What are these files used for (and <u>how did you find this out</u>)?
	# What does it mean to have execute permission on a directory?		# What does it mean to have execute permission on a directory?
	# The <tt>ls</tt> command can be used to get a listing of the files in a directory. What options are passed to <tt>ls</tt> to see: the permission bits above; all the files within a directory (including hidden files)? How to make a file hidden?		# The <code>ls</code> command can be used to get a listing of the files in a directory. What options are passed to <code>ls</code> to see: the permission bits above; all the files within a directory (including hidden files)? How to make a file hidden?
	# Compile and run [https://people.scs.~~carleton~~.ca/~~~lianyingzhao~~/comp3000/~~w23~~/tut1/csimpleshell.c <tt>csimpleshell.c</tt>]. <u>How does its functionality compare to that of <tt>bash</tt></u>? List at least 3 differences.		# Compile and run [https://people.scs.carletgon.ca/~abdou/comp3000/f23/tut1/csimpleshell.c <tt>csimpleshell.c</tt>]. <u>How does its functionality compare to that of <code>bash</code></u>? List at least 3 differences.