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+# TUM Mediasite Downloader
+
+This program is only distributed in source form and you'll need a Rust compiler to run it. See [rustup.rs](http://rustup.rs) for installation instructions.
+
+The tool accepts two arguments:
+1. a catalogue name (or an alias; see below)
+2. a target directory
+
+Most catalogues (→ lectures) require a TUMonline authentification. Those can either be supplied as environment variables or in a `.env` file (see `.example.env`; under Windows you have to rename the file to `.env.` and the last dot will be automatically removed by Windows Explorer).
+
+## Example
+
+```
+TUM_USERNAME=ab34efg TUM_PASSWORD=hunter2 cargo run -- DS ds
+```
+
+(Note: `cargo` is the the standard build tool for Rust programs. `--` passes all the following arguments to the executed program instead of interpreting them as arguments to `cargo`.)
+
+## Aliased catalogue names
+
+### WS16/17
+- `DS`
+- `EIDI` (the correct login is automatically choosen when using this alias)
+- `ERA`
+
+### SS17
+- `GAD`
+- `LA`
+
+## How to determine a catalogue name
+
+Open the Mediasite listing page, right-click and "View page source" (or "View frame source" if the listing is embedded in moodle).
+You should spot something like
+```
+<form name="MainForm" method="post" action="/Mediasite/Catalog/catalogs/17s-lineare-algebra-fuer-informatik" id="MainForm">
+```
+in the first couple of lines. Here the catalogue name would be `17s-lineare-algebra-fuer-informatik`.