# Custom Commands

Optimize repetitive terminal tasks. Custom commands, or aliases, create shortcuts for long or frequently used commands.

### Creating an Alias

Consider a common scenario: checking web server connections with a lengthy `netstat` command:

```bash
netstat -plant | grep '80\|443' | grep -v LISTEN | wc -l
```

Typing this repeatedly is inefficient. Create an alias as a shortcut. For example, let `conn` execute this command.

```bash
alias conn="netstat -plant | grep '80\|443' | grep -v LISTEN | wc -l"
```

Now, simply type `conn`:

```bash
conn
```

You'll get the same output.

Enhance it with an informative message:

```bash
alias conn="echo 'Total connections on port 80 and 443:' ; netstat -plant | grep '80\|443' | grep -v LISTEN | wc -l"
```

Running `conn` will now yield:

```
Total connections on port 80 and 443:
12
```

Note: Aliases created this way are temporary. They disappear when your terminal session ends.

### Making Aliases Permanent

Aliases are session-bound by default. To make them permanent, add them to your shell's profile file. For Bash, this is typically `~/.bashrc`.

Open `~/.bashrc` (or create it if it doesn't exist):

```bash
nano ~/.bashrc
```

Add your alias to the end of the file:

```bash
alias conn="echo 'Total connections on port 80 and 443:' ; netstat -plant | grep '80\|443' | grep -v LISTEN | wc -l"
```

Save and exit.

Apply changes without restarting your terminal:

```bash
source ~/.bashrc
```

Now, your custom command `conn` will be available in all new and sourced terminal sessions.

### Listing Aliases

To view all active aliases in your current shell, simply run:

```bash
alias
```

This helps in troubleshooting command behavior.

### Conclusion

Aliases are powerful tools for optimizing your terminal workflow, offering quick command shortcuts. While full Bash scripts offer more complexity, aliases provide an immediate, user-level solution without requiring root access for installation.

> {notice} This content was inspired by a piece by softwareshinobi on Dev Team Six.