Problem Solver
Everything is similar to the previous two videos in the series. The only difference is in this video we will learn how to use chmod with octal numbers.
In Octal
This tutorial covers how to use the chmod command to change the access permission of files and directories.
In Linux, the file is associated with an owner and a group and assigned with permission access rights for three different classes of users:
File permissions can be changed. In order to do that we make use of chmod command.
There are three file permissions that apply to each class:
-rw-r--r-- 12 yash staff 128 Oct 2 12:31 myfile.txt |[-][-][-]- [------] [---] | | | | | | | | | | | | | +-----------> 7. Group | | | | | +-------------------> 6. Owner | | | | +--------------------------> 5. Alternate Access Method | | | +----------------------------> 4. Others Permissions | | +-------------------------------> 3. Group Permissions | +----------------------------------> 2. Owner Permissions +------------------------------------> 1. File Type
Everything is similar to the previous video the only difference is we will see the behavior of directories and its contents when changing their permissions.
This tutorial covers how to use the chmod command to change the access permission of files and directories.
In Linux, the file is associated with an owner and a group and assigned with permission access rights for three different classes of users:
File permissions can be changed. In order to do that we make use of chmod command.
There are three file permissions that apply to each class:
-rw-r--r-- 12 yash staff 128 Oct 2 12:31 myfile.txt |[-][-][-]- [------] [---] | | | | | | | | | | | | | +-----------> 7. Group | | | | | +-------------------> 6. Owner | | | | +--------------------------> 5. Alternate Access Method | | | +----------------------------> 4. Others Permissions | | +-------------------------------> 3. Group Permissions | +----------------------------------> 2. Owner Permissions +------------------------------------> 1. File Type
This tutorial covers how to use the chmod command to change the access permission of files and directories.
In Linux, the file is associated with an owner and a group and assigned with permission access rights for three different classes of users:
File permissions can be changed. In order to do that we make use of chmod command.
There are three file permissions that apply to each class:
-rw-r--r-- 12 yash staff 128 Oct 2 12:31 myfile.txt |[-][-][-]- [------] [---] | | | | | | | | | | | | | +-----------> 7. Group | | | | | +-------------------> 6. Owner | | | | +--------------------------> 5. Alternate Access Method | | | +----------------------------> 4. Others Permissions | | +-------------------------------> 3. Group Permissions | +----------------------------------> 2. Owner Permissions +------------------------------------> 1. File Type
ANSI Escape Code
https://en.wikipedia.org/wiki/ANSI_escape_code#Colors
In this video, we will learn how to use the echo command. The arguments passed to echo are printed to the standard output.
Echo is commonly used in shell scripts to display a message or output the results of other commands.
Although it is not necessary to enclose arguments in double-quotes it is good practice to do so.
If using ” each character enclosed within is preserved. Variable and commands will not be expanded.
Echo can be used with pattern matching characters, such as the wildcard characters.
echo "My txt files are: *txt"
Creating a variable in the shell for the current session. Don’t leave any space between equal sign.
myString="Hello World" x=10
Display variable:
echo $myString echo "x"
Echo can redirect commands output.
echo "Directory contents: $(ls -l)"
| Command | Effect |
|---|---|
| ^O | Save changes |
| ^X | Exit nano |
When working on the command line, quite often you will need to create or edit files. Two of the most famous and powerful command-line editors are Vim and emacs. On the other hand, they are equally difficult to learn. But there is a simpler editor available to just get things done and that is nano.
All commands are prefixed with a control(^) character or metacharacter(M). caret symbol represents control and M represents Meta. Control will generally be your control key. Meta character depends on the keyboard setup. It can either be an Esc key, alt key, or a special meta key.
In this video, I will help you learn the basic usage of the nano editor, including how to create an open file, edit a file, save a file, search and replace text, cut and paste text, and more.
| Command | Effect |
|---|---|
| ^F | Forward one character |
| ^B | Back one character |
| ^Space | Forward one word |
| M-Space | Back one word |
| ^P | Previous line |
| ^N | Next line |
| ^A | Beginning of the current line |
| ^E | End of the current line |
| M-( | Beginning of the current paragraph |
| M-) | End of the current paragraph |
| M-\ | The first line of the file |
| M-/ | The last line of the file |
| ^_ | Move the cursor to a specific line |
| Command | Effect |
|---|---|
| ^W | Search pattern |
| M-W | Move to the next match |
| ^\ | Search pattern and replace |
| Command | Effect |
|---|---|
| M-A | Select text(set a selection mark) |
| ^6 | Cancel the selection press |
| M-6 | Copy the selected text to the clipboard |
| ^K | Cut the selected text |
| ^U | Paste the text at the cursor position |
| Command | Effect |
|---|---|
| ^O | Save changes |
| ^X | Exit nano |
In this video we will learn how to use rm and rmdir commands. rm stands for remove and rmdir stands for remove directory.
We will also be looking at some of the flags which can be useful along with these commands.
Flags we will learn to use are:
rmdir:
-p
rm:
-r
Thank you 🙂
angle bracket “>” is used for redirection of output from terminal to a specific file. > can be used along with any command which displays output on the terminal.
“>>” is used to append output to preexisting file.
If you have any requests for future videos you can POST them in the comments or mail it to me.
Thank you 🙂
In this video we will learn how to use cat on linux terminal. cat means concatenate and print files. We can use cat command to display content of a file. It can also be used to combine files. cat can also be used to create new files.
Flags:
-n : display line number including line breaks
-b : display line number excluding line breaks
-s : will squeeze unnecessary line breaks(leave only one line break if exist)
-e : show $ symbol at end of each line break
If you have any requests for future videos you can POST them in comments or mail it to me.
Thank you 🙂
mkdir command is used to make directory inside present working directory.
Flag:
-p : this flag is used to create tree structure directory(Example: /test/one/two/three)
If you have any requests for future videos you can POST them in comments or mail it to me.
Thank you 🙂