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--- notes:unix [2018/11/15 21:42] – [Other] sdiarra
+++ notes:unix [2020/11/04 23:50] (current) – Changed hyperlink to secure variant smalik3
@@ Line 5: / Line 5: @@
 </WRAP>
-======Projects======
+======Course Notes======
-======URLs======
+The "man" command can be used on Linux to display the manual of an inputted command. To use this command type "man" followed by a space and then a Linux command.
-**Linux Kernel-Repo (Linus Torvalds)**
+Example: <code>man cd</code>
-https://github.com/torvalds/linux
+This will display the manual for the Linux command "cd". This is very useful for starting off understanding Linux commands. And when in more doubt [[https://www.google.com|Google]] or asking questions to your professor is the answer.
-======Notes======
--------
-I feel like there should be some beautiful words of knowledge contained on this page, so I have decided to do my best attempt at making it that way.
-===Vim/Vi Command Mode Commands===
+----------------------------------
-- Escape key leads to command mode.
+The "cd" command is useful for going into directories or folders.
+Example: <code>cd</code>
+After using "cd" you add the option if which directory/folder you want to go into. Such as "cd familyphotos", you can even get to directories not close to the one you're in like "cd ~/games/somegame/unrelated".
-- 'i' leads to insert mode at the current space.
+----------------------------------
-- Navigation is accomplished through h (right), j (down), k (up), l (left).
-- 'a' leads to insertion mode at the next space.
+The "mkdir" command is useful for creating folders.
+Example: <code>mkdir</code>
+After using "mkdir" you add the name of the folder. For example "mkdir folder" will create a folder named "folder" in whatever directory you are in. You can also use full paths like "mkdir ~/classes/unix" to create a folder that may not be in the same directory as you.
-- 'I' leads to insert mode at the beginning of the line.
-- 'A' leads to insert mode at the end of the line.
-- 'o' leads to insert mode on a new line after the current line.
-- 'O' leads to insert mode on a new line before the current line.
-- 'w' is move forward a word (stop not just at spaces, but also / . , ? and more).
-- 'b' is move back a word (same as above).
-- 'W' and 'B' move forward and backward a word (only stop at spaces).
-- '.' repeats the last command.
-- '^' and '$' take you to the beginning and end of lines respectively without going into insert mode.
-- '{' and '}' take you to the previous and next paragraphs. [Side Note: many of these commands can be prefixed
-with a number, which means you want the command to be executed that many times].
-- 'x' deletes the next character.
-- 'X' is cutting (acts like backspace).
-- You can also do commands like dw, db, d^, d$, d{, d}, dd which do a delete operation related to the letter after the 'd' (dd deletes the current line).
-- 'v' allows you to highlight text by moving around with the arrow keys.
-- 'y' is yank (essentially just 'copy'). There must be text highlighted for this to work.
-- 'p' pastes below and 'P' pastes above.
--------
-<color #ed1c24>Regular expressions</color>
-In a sort of a related note, as vi uses some regular expressions patterns, this section will cover regular expressions and pattern matching. In Unix regular expressions are used to give a user/admin the capability to search based on patterns. Regular expressions, or regex, or regexp is a very useful tool. The common patterns are the followings:
-- '.' --> indicates match every characters
-- '^' --> match the beginning of a string or file(As in Vi)
-- '$' --> match the end of a line of file(As in Vi)
-- '[a-zA-Z]' --> match all letters uppercase and lowercase
-- '[0-9]' --> match only digits from 0-9
-- '[0-9]*' --> match 0 or more digits
-- '[0-9]+' --> match 1 or more digits
-- '[a-d]?' --> match 0 or only one occurrence of a-d lowercase
-- '[0-9]{x, y}' --> match digits at least x times, and less than y times
-*These are few common patterns in regex.
-======Other======
--------
-<color #ed1c24>Quick Tip: </color>
-Recently I have discovered a trick that could help run scripts much quicker with direct access to one's lab46 account, without working only on a single a single. Ultimately, I had to ssh into my account, and whenever I left the terminal open for a few minutes, it would go offline - or had share scripts between my personal laptop and lab46 machines, and work on projects on one machine at a time(fairly painful). With this method one can easily call commands anywhere, that are otherwise only available on the lab46 account. Here is how it is accomplished:
-<code>
-    ssh account@lab47.corning-cc.edu command_here
-</code>
-A working example would be the following:
-<code>
-     #From my own laptop
-     current_grades=$(ssh user@lab46.corning-cc.edu status unix)
-     #This example would return grades from the user.
-</code>
-**Note that the script would prompt you to enter your <color #ed1c24>password</color>.**