Using Mrxvt with Dtach
Roger
roger<at>eskimo.com
http://www.eskimo.com/~roger/programming/mrxvtanddtach.html
2006.09.16
This document will instruct how to setup Mrxvt using Dtach to
manage each tabbed session.
Contents
Introduction
What is Mrxvt and Dtach? Mrxvt is a
branch of code from the Rxvt
Terminal project integrating the tabbed feature into the terminal as
well as other features. Dtach is similar to the "GNU
Screen" project but tiny and easy! With these two features, a
user can have tabbed
detached sessions. (This is very similar to the feature Eterm is
hard coded using GNU Screen!)
The pros of using Mrxvt with Dtach over Eterm's implementation of GNU
Screen are:
- Mrxvt has better font support including xft fonts
- Mrxvt uses about a half megabyte less memory when compared to
Eterm's memory usage
- Dtach omits stripping your shell of any special keys
- Dtach is easier to use when compared to GNU Screen's many complex
features
If you don't know what
GNU Screen or Dtach is, the big plus with using detached terminals, if
you're compiling code and your terminal segfaults on you, whatever you
were doing in your terminal, is still working in a background process
separate of you terminal. In theory, restarting your terminal and
reattaching to the previous session should redisplay your current
compile still performing or Irssi session without interruption!
Don't get me wrong. I've used Eterm with GNU Screen for the past
years and life would have been extremely difficult rebuilding my Gentoo
boxes without it. But there are allot of features of GNU Screen
the basic shell user just isn't going to use. For the time being,
I'm giving Mrxvt & Dtach a whirl.
One issue with Dtach, Dtach does not redraw the screen as GNU Screen
would. This is one of the first things mentioned on the Dtach
homepage.
Dtach Install and Setup
Dtach setup is quite
easy. Emerge or install Dtach according to your distribution's
package install procedures.
Using Gentoo:
# emerge
dtach
Mrxvt
Install and Setup
Emerge or install Mrxvt
according to your distribution's package install procedures.
Using
Gentoo:
# emerge
mrxvt
To setup a Mrxvt Terminal, the user either needs a ~/.mrxvtrc file or needs to specify
all their configurations via command line switches. To simplify this
process, you can copy and modify my ~/.mrxvtrc file into your own $HOME
folder.
Running Mrxvt with Dtach
$ mrxvt -name default
&
The above command line starts a Mrxvt terminal with a default profile
and is best
placed within either your ~/.xprofile, ~/.e16/Init/sessions.sh or other window manager
startup
file.
The "-name default"
starts a Mrxvt with a group of tabs specified by the default profile
listed within the ~/.mrxvtrc
file. The "default" profile will also execute dtach within each
tabbed shell - specifying a unique socket file to attach and reattach
to
as needed. (Mrxvt's tabbed profiles was one of the more difficult
features to configure. Configuring eye-candy features was, at
most, trivial.)
The idea is, if
your
window manager segfaults, on restart of X
or your window manager will result in your terminals being
reattached. (If you're compiling Openoffice or other package,
your
compile should still be performing independentaly in a detached process
apart of your window manager or other graphical terminal interface and
the compile should simply reappear in your terminal on restart using
the above mrxvtrc and command line flags.)
*Be aware of Dtach trying to use old or stale socket files! See
Troubleshooting to ensure after a reboot, you're starting Mrxvt with
clean Dtach sockets.
Troubleshooting
At times, you may find
Dtach not cleaning-up it's old socket files or not able to create a new
one for some reason. This may happen if
your Dtach session encounters an unexpected segfault or your computer
reboots unexpectedly. A way I work around this, before starting
Mrxvt, I'll remove any old or stale Dtach socket files with the
following:
$ rm -f
/tmp/dtach.roger-* && DISPLAY=":0.0" mrxvt -name default
&
Again, the above goes
into my window manager's start up file. ie. ~/.e16/Init/session.sh
However, this defeats
the purpose when X crashes. From the dtach man file, "-A" should
recognize a stale socket file and just create a new one. I'm sure
this is basically a bug bound to be fixed in future versions.
Screenshot
This screenshot isn't
going show-off the features or benefits of Dtach as the features of
Dtach are transparent and only seen on detach of a session or
segfault. This will, however, give you a good idea of the look
&
feel of the ~/.mrxvtrc
file. (For transparency, I have Xorg's Composite module
performing all transparency operations for all applications using Xorg.)
