status: #doc 
Tags: #linux
links:
Date: 2023-11-07
___
# linux commands

## list
#### list with details
```sh
ls -ltrh
```

## make and destroy

### directory
#### make directory 
```sh
mkdir
```
#### delete directory 
```sh
rmdir
```

## find command locatiozn

```bash
whereis
```

## zip

### ziping

for 1 file
```zsh
zip zipfilename.zip what_to_zip_file  
gzip  zipfilename.zip what_to_zip_file  
```

for folder
```zsh
zip -r zipfilename.zip what_to_zip_folder  
gzip -r zipfilename.zip what_to_zip_folder  
```
### unzip

```shell
unzip
gunzip
```

## user mangmet

### user

* see encrypted users password
```sh
cat etc/shadow
```

1. **useradd:**
   - Adds a new user to the system.
   ```bash
   sudo useradd username
   ```

2. **passwd:**
   - Changes the password for a user.
   ```bash
   sudo passwd username
   ```

3. **userdel:**
   - Deletes a user account.
   ```bash
   sudo userdel username
   ```

4. **usermod:**
   - Modifies user account properties.
   ```bash
   sudo usermod options username
   ```

5. **id:**
   - Displays user and group information for a specified username.
   ```bash
   id username
   ```
7. **passwd -e:**
   - Expire a user's password immediately, forcing them to change it on the next login.
   ```bash
   sudo passwd -e username
   ```

### usermod options


Certainly! Here's the text with the content changed to a numbered list:

1. **Changing the Username:**
    ```bash
    sudo usermod -l newusername oldusername
    ```

2. **Changing the User ID (UID):**
    ```bash
    sudo usermod -u newuid username
    ```

3. **Changing the Home Directory:**
    ```bash
    sudo usermod -d /new/home/directory username
    ```

4. **Changing the Default Shell:**
    ```bash
    sudo usermod -s /path/to/new/shell username
    ```

5. **Adding a Supplementary Group:**
    ```bash
    sudo usermod -aG newgroup username
    ```

6. **Locking/Unlocking an Account:**
    ```bash
    sudo usermod -L username   # Lock the account
    sudo usermod -U username   # Unlock the account
    ```

7. **Expiring a User Account:**
    ```bash
    sudo usermod -e YYYY-MM-DD username
    ```

8. **Forcing Password Change on Next Login:**
    ```bash
    sudo usermod -e 1 username
    ```

9. **see expire date of user and password:**
	```bash
	sudo usermod -l newusername 
	```
 
### groups

Here are some common commands related to managing user groups in Linux:

1. **groupadd:**
   - Adds a new group to the system.
   ```bash
   sudo groupadd groupname
   ```

2. **groupdel:**
   - Deletes a group from the system.
   ```bash
   sudo groupdel groupname
   ```

3. **groupmod:**
   - Modifies group properties.
   ```bash
   sudo groupmod options groupname
   ```

4. **gpasswd:**
   - Adds or removes users from a group.
   ```bash
   sudo gpasswd -a username groupname  # Add user to group
   sudo gpasswd -d username groupname  # Remove user from group
   ```

5. **groups:**
   - Displays the groups a user belongs to.
   ```bash
   groups username
   ```

6. **newgrp:**
   - Switches the primary group.
   ```bash
   newgrp groupname
   ```

7. **getent group:**
   - Displays information about groups from the system databases and Name Service Switch sources.
   ```bash
   getent group
   ```

### file
Managing file ownership and permissions is an important aspect of user management in Linux. Here are some commands related to user management for files:

1. **chown:**
   - Changes the owner of a file.
   ```bash
   sudo chown username:groupname file
   ```

2. **chgrp:**
   - Changes the group ownership of a file.
   ```bash
   sudo chgrp groupname file
   ```

3. **chmod:**
   - Changes the permissions of a file.
   ```bash
   sudo chmod permissions file
   ```

   The `permissions` can be represented in octal or symbolic notation. For example:
   ```bash
   sudo chmod 755 file    # Give read, write, and execute to owner; read and execute to group and others
   ```

4. **ls:**
   - Lists files and their permissions.
   ```bash
   ls -l file
   ```

   Example output:
   ```
   -rwxr-xr-x 1 username groupname 1234 Nov 21 12:34 file
   ```

   The first field represents the file type and permissions.

5. **umask:**
   - Sets the default permissions for newly created files.
   ```bash
   umask 022
   ```

   This example sets the default permissions to `rw-r--r--` for newly created files.








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# References