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    "# Maneuvering directories (i.e. folders)\n",
    "\n",
    "To get some practice with the command line, we will use an example directory with some files in it. You can download a ZIP file containing the directory [here](https://s3.amazonaws.com/bebi103.caltech.edu/data/command_line_recitation.zip).\n",
    "\n",
    "And we said we would use the terminal in Jupyter Lab, so let us open a terminal (another one!) and type `jupyter lab`. If you do not have Jupyter Lab installed, just use your normal terminal and install it after the class.\n",
    "Once Jupyter Lab opens in your browser you can open `File -> New -> Terminal`."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## pwd and ls\n",
    "\n",
    "When the shell is ready for your input it will display a `$` at the beginning of the line, which means that you are a normal user (not an admin) and the terminal is ready.\n",
    "Let's start out by using the `pwd` command to figure out what directory we're in.\n",
    "\n",
    "    pwd\n",
    "\n",
    "`pwd` tells you the **path** of your current directory.  A path for a directory or file is the list of all its parent directories, separated by slashes (`/`), up to the root directory signified by the initial `/`.  You are probably in your home directory.\n",
    "\n",
    "To list all files and folders in the current directory, we employ the `ls` command.\n",
    "\n",
    "    ls"
   ]
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   "metadata": {
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   "source": [
    "## cd: change directory\n",
    "Let's make sure we are in the home directory:\n",
    "\n",
    "    cd\n",
    "\n",
    "Use `pwd` to check where you are now. Invoking the `cd` command without specifying a target directory defaults to the home directory. Another way to specify your home directory is by its shortcut, `~/`. In general, the tilde-slash means \"home directory.\" \n",
    "\n",
    "From here, let's navigate to the `command_line_recitation` directory:\n",
    "\n",
    "    cd command_line_recitation\n",
    "    \n",
    "Note, that depending on where you saved this directory, you may have to do some additional navigation to get to it. For example, anything I download defaults to the `Downloads` directory, so I would navigate by:\n",
    "\n",
    "    cd Downloads/command_line_recitation\n",
    "    \n",
    "It's important to know that you can either specify the **full** path (beginning with your home directory) to the directory you want to navigate to or you can enter the **relative** path starting from your current directory.\n",
    "\n",
    "**HINT**: if you have changed directory and need to come back to where you were before, you can just type:\n",
    "    \n",
    "    cd -\n",
    "\n",
    "This will get you back to the previous directory quickly and without specifying the path."
   ]
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   "metadata": {},
   "source": [
    "## mkdir and rmdir\n",
    "\n",
    "To make a directory, the command is `mkdir`, hence the name ***m***a***k***e ***dir***ectory. followed by the name of the directory you want to create. For example, to make a directory called `rec01`:\n",
    "\n",
    "    mkdir rec01\n",
    "    \n",
    "You now have an empty directory called `rec01`. You can see it if you list the contents of the directory.\n",
    "\n",
    "    ls\n",
    "    \n",
    "We do not need (nor want) this directory, since this is just for practice, so let's delete it. To delete an *empty* directory, the command is `rmdir`.\n",
    "\n",
    "    rmdir rec01\n",
    "    "
   ]
  },
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   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br />\n",
    "\n",
    "*Copyright note: In addition to the copyright shown below, this recitation was developed based on materials from Axel Müller.*"
   ]
  }
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