143 lines
4.2 KiB
Markdown
143 lines
4.2 KiB
Markdown
title: Emacs server the fun way
|
|
---
|
|
pub_date: 2020-04-23
|
|
---
|
|
author: Nico Schottelius
|
|
---
|
|
twitter_handle: NicoSchottelius
|
|
---
|
|
_hidden: no
|
|
---
|
|
_discoverable: yes
|
|
---
|
|
abstract:
|
|
Let's dive into a very nice emacs feature
|
|
---
|
|
body:
|
|
|
|
Today I want to talk about how amazing emacs is. Not because it is the
|
|
most feature complete operating system out there or because
|
|
[it fully emulates vi/vim](https://github.com/emacs-evil/evil).
|
|
No, because emacs has a very nice feature called **emacs server**.
|
|
|
|
## What's an emacs server?
|
|
|
|
If emacs is not an operating system, at least emacs stands for
|
|
"**e**ight **m**egabytes **a**nd **c**onstantly **s**wapping", doesn't
|
|
it? (This is actually from times where 8 megabytes were quite a lot of
|
|
memory)
|
|
|
|
So why do people make fun of emacs and how is it related to the emacs
|
|
server?
|
|
Emacs, like any other operating system, loads a lot of things at
|
|
startup. In my case this is initialising
|
|
[org-mode](https://orgmode.org/), starting my mail client, calculating
|
|
my agenda view to tell me what to do today.
|
|
|
|
An emacs server creates a special emacs process that listens on a
|
|
socket for connecting to it. This way the initialisation is already
|
|
done before you connect to it and all
|
|
configurations are already loaded. This is the actual "slow" part of
|
|
emacs. And is a bit similar to starting python, which also needs to
|
|
load its libraries at start.
|
|
|
|
With the emacs server running, you can connect to it using the
|
|
**emacsclient** program.
|
|
|
|
As a matter of fact,
|
|
[rxvt-unicode](http://software.schmorp.de/pkg/rxvt-unicode.html) also
|
|
knows about a server mode (checkout the manpage, look for
|
|
**urxvtd -q -f -o**). For rxvt-unicode, you'd use **urxvtc** to
|
|
connect to it. So quite simlar.
|
|
|
|
## What is so cool about the emacs server?
|
|
|
|
Saving a lot of response time and making working with emacs **feel**
|
|
much faster is the obvious advantage. However, there is a much bigger
|
|
one:
|
|
|
|
With the emacs server, you can connect to it from the terminal **and** X
|
|
Windows. Because the emacs server also manages the buffers ("open
|
|
files" for non-emacs users), you can view the same open file from the
|
|
terminal or an x window.
|
|
|
|
## Turning the notebook into a server
|
|
|
|
As you might now, we at ungleich are pretty much into IPv6. So all of
|
|
our devices are generally speaking world-wide reachable. Our work
|
|
notebooks are no exception from that. In fact, most notebooks even
|
|
have their own [/48 IPv6 network assigned via
|
|
VPN](/u/products/ipv6-vpn/).
|
|
|
|
So if I am away from my notebook, but need to check my open (and
|
|
potentially unsaved) notes or view my emails, I can use any other
|
|
computer, ssh to my notebook and type **emacslient -nw** in the
|
|
terminal.
|
|
|
|
While my regular emacs is running as an X11 window, I can select,
|
|
display and work in all buffers that I have previously opened in the
|
|
emacs server. In the terminal, on a remote computer.
|
|
|
|
## How to configure your system to use the emacs server
|
|
|
|
In my case I start the emacs server when I start X11 in my .xinitrc:
|
|
|
|
```
|
|
eval $(ssh-agent)
|
|
...
|
|
urxvtd -q -f -o
|
|
emacs --daemon
|
|
...
|
|
```
|
|
|
|
Instead of running emacs --daemon, you can also use **M-x
|
|
server-start** in a running emacs process.
|
|
|
|
And because I always want to have my mail client open, just after I start
|
|
i3, I have i3 launch the following command:
|
|
|
|
```
|
|
ssh-add </dev/null && emacsclient -c -e '(mu4e)'
|
|
```
|
|
|
|
The connection to my mailserver is tunneled via SSH to prevent
|
|
security issues from using SSL/TLS. Thus I need to add all my ssh keys
|
|
to the ssh-agent, before starting my mail client.
|
|
|
|
To actually open a new emacs windown (aka "frame" in emacs speech), I
|
|
use the following configuration in my **~/.i3/config**:
|
|
|
|
```
|
|
bindsym $mod+Tab exec emacsclient -c
|
|
```
|
|
|
|
## How does this look like?
|
|
|
|
Below you find a screenshot of my writing this article. The upper
|
|
window is the X11 window, the lower window is a terminal window (they
|
|
happen to be configured to have the same nice background colour).
|
|
|
|
|
|
|
|
|
|
## Updates
|
|
|
|
### 2020-04-23, 17:23
|
|
|
|
[MutoShack](https://www.reddit.com/user/MutoShack/) pointed
|
|
out on
|
|
[reddit](https://www.reddit.com/r/emacs/comments/g6nqwv/emacs_server_the_fun_way/foazghz/)
|
|
that using
|
|
|
|
```
|
|
emacsclient -a "" -c
|
|
```
|
|
|
|
is actually smarter than just using
|
|
|
|
```
|
|
emacsclient -c
|
|
```,
|
|
|
|
because it will start the daemon if it is not already running. No day
|
|
that you don't learn something!
|