# Nerves.Runtime
[](https://travis-ci.org/nerves-project/nerves_runtime.svg)
[](https://hex.pm/packages/nerves_runtime)
Nerves.Runtime is an optional component of Nerves but it's really handy and has
a small footprint. Here are some of its features:
* A custom shell for debugging and running commands in a `bash` shell like
environment
* A small Linux kernel `uevent` application for capturing hardware change events
and more
* More to come...
## The Nerves Runtime Shell
Nerves devices typically only expose an Elixir or Erlang shell prompt. While
this is handy, so tasks are quicker to run in a more `bash` shell-like
environment. The Nerves runtime shell provides a limited approximation to this
that can be run without leaving the Erlang runtime. Here's an example run:
```
iex(1)> [Ctrl+G]
User switch command
--> s sh
--> j
1 {erlang,apply,[#Fun<Elixir.IEx.CLI.1.112225073>,[]]}
2* {sh,start,[]}
--> c
Nerves Interactive Command Shell
Type Ctrl+G to exit the shell and return to Erlang job control.
This is not a normal shell, so try not to type Ctrl+C.
/srv/erlang[1]>
```
There are a few caveats to using this shell right now, so you'll have to be
careful when you use it:
1. `Ctrl+C Ctrl+C` exits the Erlang VM and will reboot or hang your system
depending on how `erlinit` is configured.
2. Because of the `Ctrl+C` caveat, you can't easily break out of long running
programs. As a workaround, start another shell using `Ctrl+G` and `kill` the
offending program.
3. Commands are run asynchronously. This is unexpected if you're used to a
regular shell. For most commands, it's harmless. One side effect is that if a
command changes the current directory, it could be that the prompt shows the
wrong path.
## Installation
The package can be installed
by adding `nerves_runtime` to your list of dependencies in `mix.exs`:
```elixir
def deps do
[{:nerves_runtime, "~> 0.2.0"}]
end
```
Docs can be found at [https://hexdocs.pm/nerves_runtime](https://hexdocs.pm/nerves_runtime).
