> For the complete documentation index, see [llms.txt](https://www.pythonclassroom.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.pythonclassroom.com/python-cloud-options/cloud9/linux-bash-shell.md).

# Linux Bash Shell

CS50 IDE is currently using Ubuntu 18 LTS

```bash
$ cat /etc/*release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=18.04
DISTRIB_CODENAME=bionic
DISTRIB_DESCRIPTION="Ubuntu 18.04.3 LTS"
```

## Terminal Shortcuts

| Key/Command | Description                                                                       |
| ----------- | --------------------------------------------------------------------------------- |
| ctrl-a      | Go to the beginning of the line you are currently typing on.                      |
| ctrl-c      | Kill whatever you are running. Also clears everything on current line             |
| ctrl-e      | Go to the end of the line you are currently typing on.                            |
| ctrl-l      | Clear the terminal                                                                |
| ctrl-r      | Reverse search history                                                            |
| ctrl-w      | Delete word on the left                                                           |
| ctrl-y      | Paste                                                                             |
| ctrl-z      | Puts whatever you are running into a suspended background process. fg restores it |
| tab         | auto completion of file or command                                                |
| !!          | repeat last command                                                               |

## Terminal Navigation

| Key/Command        | Description                   |
| ------------------ | ----------------------------- |
| ls -a              | list all files and folders    |
| ls \<foldername>   | list files in folder          |
| ls -lh             | Detailed list, human readable |
| ls -l \*.jpg       | list jpeg files only          |
| ls -lh \<filename> | Result for file only          |
| cd \<foldername>   | change direcxtory             |
| cd /               | goto root directory           |
| cd ..              | go up one folder              |
| pwd                | print working directory       |
| man \<command>     | shows manual                  |

## Pipe

| Key/Command                  | Description                                                                      |
| ---------------------------- | -------------------------------------------------------------------------------- |
| \[command-a] \| \[command-b] | Run command A and then pass the result to command B e.g ps auxwww \| grep google |

## File Manipulation

### tail

| Key/Command         | Description                            |
| ------------------- | -------------------------------------- |
| tail \<filename>    | output the last part of files          |
| tail -f \<filename> | output appended data as the file grows |

### head

| Key/Command         | Description                                       |
| ------------------- | ------------------------------------------------- |
| head \<filename>    | output the first part of files                    |
| head -n \<filename> | print the first NUM lines instead of the first 10 |

### cp

| Key/Command                | Description                     |
| -------------------------- | ------------------------------- |
| cp image.jpg newimage.jpg  | copy and rename a file          |
| cp image.jpg \<foldername> | copy to a folder                |
| cp -R stuff otherstuff     | copy and rename a folder        |
| cp \*.txt stuff            | copy all \*.txt to stuff folder |

### cat

| Key/Command     | Description                                        |
| --------------- | -------------------------------------------------- |
| cat \<filename> | concatenate files and print on the standard output |

### mkdir

| Key/Command         | Description        |
| ------------------- | ------------------ |
| mkdir \<foldername> | create a directory |

### redirect

| Key/Command           | Description                                               |
| --------------------- | --------------------------------------------------------- |
| \[command] > \[file]  | Push output to file, keep in mind it will get overwritten |
| \[command] >> \[file] | Append output to existing file                            |
| \[command] < \[file]  | Tell command to read content from a file                  |

### touch

| Key/Command       | Description            |
| ----------------- | ---------------------- |
| touch \<filename> | change file timestamps |

##


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