Adds more commands into basic_cmd.md

Linux/basic_cmd.md

@@ -22,15 +22,15 @@ If you see all these paths started from / directory which is a root directory fo
 Relative path is defined as path related to the present working directory(pwd). Suppose I am located in /var/log and I want to change directory to /var/log/kernel. I can use relative path concept to change directory to kernel
 
 changing directory to /var/log/kernel by using relative path concept.
-
+```bash
-> $ pwd/var/logcd kernel
+ $ pwd/var/logcd kernel
- 
+``` 
 Note: If you observe there is no / before kernel which indicates itâs a relative directory to present working directory.
 
 Changing directory to /var/log/kernel using absolute path concept.
-
+```bash
-> $ cd /var/log/kernel
+ $ cd /var/log/kernel
- 
+``` 
 Note: We can use an absolute path from any location where as if you want to use relative path we should be present in a directory where we are going to specify relative to that present working directory.
  
 Examples of relative path and absolute path for the same operation.
@@ -38,14 +38,18 @@ Examples of relative path and absolute path for the same operation.
 # Basic Linux Command
 
 ## help
-- Man: an interface to the on-line reference manuals 
+
-> $ man ls
+###  Man: an interface to the on-line reference manuals 
+```bash
+ $ man ls
+```
 
 ## Wildcard
-* Show all picture (multiple char)
+### \* Show all picture (multiple char)
+```bash
 > $ ls pic*  
 
-? show only picture between 50 and 59 (only one char)
+### **?** show only picture between 50 and 59 (only one char)
 
 > $ ls pic5?.jpg  
 
@@ -78,56 +82,80 @@ back to previous folder
 
 -p to create parent directory if needed
 
-- Rmdir: Remove directory
+### Rmdir: Remove directory
+```bash
+ $  rmdir filename
 
-> rmdir filename
+ $ rm -rf filename
-
+```
-> rm -rf filename
 
 Delete all of the files in the diectory including all subdirectories and tier contents
-> $ rm -r \* .\*  
+```bash
+ $ rm -r \* .\*  
+```
 
 Remove all files with the .doc extension recursively in the current working directory.
-> $ rm \*\*/\*.doc
+```bash
+ $ rm \*\*/\*.doc
+```
 
+### Mv: Move directory (can be used to rename a file)
+```bash
+ $  mv file /opt/movedfile
+```
 
-- Mv: Move directory (can be used to rename a file)
+### Cp: Copy file or directory
-> mv file /opt/movedfile
+```bash
+ $ cp file /opt/newcopiedfile 
+```
 
-- Cp: Copy file or directory
+### Touch: change file timestamps but it can also create files   
-> $ cp file /opt/newcopiedfile 
+```bash
+ $ touch nomdefichier.md  
 
-- Touch: change file timestamps but it can also create files   
+ $ touch pic{00..99}.jpeg # does not work
-> $ touch nomdefichier.md  
+```
-
-> $ touch pic{00..99}.jpeg # does not work
   
-- Which: Searching the PATH for executable files matching the names of the arguments
+### Which: Searching the PATH for executable files matching the names of the arguments
-> $ which ls
+```bash
-
+ $ which ls
-- File: file — determine file type
+```
-> $ file myfile
+### File: file — determine file type
-
+```bash
+ $ file myfile
+```
 ## file viewer
-- More: file perusal filter for crt viewing
 
-> $ more filename 
+### More: file perusal filter for crt viewing
+```bash
+ $ more filename 
+```
+###  Less: opposite of more but Less is more ;)
+```bash
+ $ less filename
+```
+###  Cat: concatenate files and print on the standard output
+```bash
+ $ cat filename
+```
+### tail : output the last part of files
 
-- Less: opposite of more but Less is more ;)
+```bash
+$ tail -n 5 Workspace/SysAdminTraining/LinuxSysAdminsDoc/Linux/basic_cmd.md 
+- dhclient > get ip
+- gnome networkmanager 
+- wpa_supplicant > encryption @ wifi
 
-> $ less filename
+![htop](./img/htop.png)
-
+```
-- Cat: concatenate files and print on the standard output
-
-> $ cat filename
 
+Args -n define the number of line needed 
 ## Users
 
 adduser, addgroup - add a user or group to the system
-> sudo adduser steve
 
 ```bash
-r4v3n@d3bi4n:~/Workspace/test$ sudo adduser steve
+ $ sudo adduser steve
 [sudo] password for r4v3n: 
 Sorry, try again.
 [sudo] password for r4v3n: 
@@ -258,15 +286,54 @@ marie steve
 
 ## Sysadmin tools 
 
-- How to create a symbolic link in Linux
+### & vs &&
+```bash
+ $ apt update && upgrade
+# && launch both instance one after the other
+ $ sleep 10 & htop
+& launch in background the sleep 10 process and open htop
+```
+### exit status
+```bash
+ $ ls thisnotexist
+ls: cannot access 'thisnotexist': No such file or directory
+ $ echo $?
+2
+ $ ls
+Desktop  Documents  Downloads  Music  Pictures  Public  Templates  Videos  Workspace
+ $ echo $?
+0
+r4v3n@d3bi4n:~$ 
+
+```
+### Display Environement variables
+```bash
+ $ env
+SHELL=/bin/bash
+XDG_CURRENT_DESKTOP=GNOME
+...
+```
+### Get users password hases:
+```bash
+ $ cat /etc/shadow | grep bash
+ # get hashes
+ $ sudo cat /etc/shadow | cut -d ":" -f2
+ # get name
+ $ sudo cat /etc/shadow | cut -d ":" -f1
+```
+### How to create a symbolic link in Linux
 To create a symbolic link to target file from link name, 
 you can use the ln command with -s option like this:
-
+```bash
-> ln -s target_file link_name
+ $ ln -s target_file link_name
-
+```
+### alias:
+```bash
+ $ alias ll="ls -l"
+```
 The -s option is important here. It determines that the link is soft link. If you don’t use it, it will create a hard link. I’ll explain the difference between soft links and hard links in a different article.
 
-- Htop: Interactive processes viewer
+### Htop: Interactive processes viewer
 > $ htop
 
 - Changer default shell
@@ -312,7 +379,7 @@ $ realpath example.txt
 
 - Wget: The non-interactive network downloader
 
-```
+```bash
  $ wget www.tandemlaw.be 
 ```
 - search url inside index.html
@@ -325,10 +392,10 @@ $ cat index.html | grep -o "https.*" |cut -d "\"" -f1 |sort | uniq
 - Nano: Nano's ANOther editor, an enhanced free Pico clone
 (simple text editor for noobies) 
 
-> $ nano 
+```bash
-
+ $ nano 
-> $ nano filename
+ $ nano filename
-
+```
 - VIM: vim - Vi IMproved, a programmer's text editor (PGM)
 
 > $ vim
@@ -336,42 +403,46 @@ $ cat index.html | grep -o "https.*" |cut -d "\"" -f1 |sort | uniq
 > $ vim filename   
 
 # APT
-> $ apt install
+```bash
-> $ apt remove
+  $ apt install
-> $ apt autoremove
+  $ apt remove
-> $ apt update
+  $ apt autoremove
-
+  $ apt update
+```
 
 ## Display & Destop Manager
 
 * Architecture:
-> BIOS -> GRUB -> Display Manager -> Desktop Environement
+```bash
-
+ BIOS -> GRUB -> Display Manager -> Desktop Environement
+```
 * Install Desktop Environement (GUI)
-
+```bash
-> $ tasksel
+ $ tasksel
-> $ apt install gnome
+ $ apt install gnome
-> $ apt remove gnome
+ $ apt remove gnome
+```
 
 * Reconfigurer le display manager
-> $ sudo dpkg-reconfigure gdm3
+```bash
+ $ sudo dpkg-reconfigure gdm3
+```
 
 * Installer le display manager
 
-> $ sudo apt install lightdm
+```bash
-
+ $ sudo apt install lightdm
-> $ sudo apt install gdm3
 
+ $ sudo apt install gdm3
+```
 * remove Desktop environement
-
+```bash
-> $ sudo apt remove lightdm 
+ $ sudo apt remove lightdm 
-
+```
 # Services 
 - HTOP
 - dhclient > get ip
 - gnome networkmanager 
 - wpa_supplicant > encryption @ wifi
 
-# note : add HTOP picture (use f5)
-
 ![htop](./img/htop.png)