At the heart of every Unix and Linux desktop is the X Window
system (also referred to as just X). It’s a heart that, now with the X.org
7.3 release, adds a number of new features including input hot-plugging
support.
While hot plugging, the ability to plug something in while the
system is already running and have it be detected, might not sound like
something new, it is new to X.
“The ability to hot-plug basically anything has never worked before in X,”
Guy Lunardi, product manager for SUSE Linux Enterprise Desktop, Novell told
InternetNews.com. “In the recent past, the Linux kernel has been
taking care of the hot-plug of input devices. The X server had really no
knowledge of those new devices.
“With the X server being capable of knowing
about when devices are added or removed is a huge improvement,” Lunardi continued. “Not only does
that apply to input devices, but monitors are also detected and added on the
fly as well without requiring the user to log out or anything.”
Though input hot plugging may seem like something that is widely required, it
took the efforts of someone with a particular need for this solution.
According to X developer and Intel employee Keith Packard, that person was
Daniel Stone, working at Nokia on the N770 and N800 projects.
“Those devices [Nokia’s] are often dynamically connected to different
keyboards, which turns out to be the interesting part of input hot-plugging, as
different keyboards have different symbols on some keys,” Packard explained
to InternetNews.com.
“Until now, most people have only needed to
hot-plug pointer devices, mice, touch pads, etc. As the Linux kernel can
merge these devices together, things worked fairly well without X support.”
Since 2004, X.org has been the leading organization behind the development of
X. The X Window System is an open source-licensed windowing system
(graphical user interface) for Unix and Linux platforms and is essentially a standard library of routines that can be used to develop GUI applications and open source desktop environments.
Nearly every modern Unix and Linux operating
system uses X as the foundation for its desktop system.
Among the users of X is Sun’s Solaris. Stuart Kreitman, software engineer at
Sun Microsystems, explained that Sun has had hot-plugged input devices for a
while now.
“Semi-automatic hot plug of graphics displays (e.g. projector attached to
laptop) is something relatively new, yet even there, we have been part of
the X.org conversations on how it might get done,” Kreitman told
InternetNews.com.
Kreitman and Novell’s Lunardi were also keen on another aspect of the X.org
7.3 release, called Xrandr1.2, which allows dynamic screen resize and rotate, and attachment of new screens on the fly.
For Intel’s Packard the best part of the release has been the release process
itself.
“We set out with release 7.0 to create a process where releases would no
longer be an onerous task taking weeks of developer effort, and with 7.3,
we’ve finally reached that goal,” Packard said.
“Eric Anholt, our release
wrangler for 7.3, worked with the X.org community to ensure that the many
pieces that make up X.org 7.3 were packaged and ready to ship. With the
individual pieces prepared, the release process now devolves to collecting
the pieces together and making the release announcement.”
With the 7.3 release out the door, there are is still a long list of items
that Packard wants to get done with X.org.
“Our biggest changes ahead are tighter integration with the kernel, improved
memory management and better media acceleration,” Packard said. “Kernel
integration will bring improved suspend/resume support, on-screen kernel
messages and faster boot times.”
