7.3.2.1. Display names
From the user's perspective, every X server has a display
name in the form of:
hostname:displaynumber.screennumber
This information is used by the application to determine how it
should connect to the X server and which screen it should use by
default (on displays with multiple monitors):
-
hostname: The host name specifies the name of the
client machine to which the display is physically connected. If the
host name is not given, the most efficient way of communicating to
a server on the same machine will be used.
-
displaynumber: The phrase "display" is usually used to refer to a collection
of monitors that share a common key board and pointer (mouse,
tablet, etc.). Most workstations tend to only have one keyboard,
and therefore, only one display. Larger, multi-user systems,
however, frequently have several displays so that more than one
person can be doing graphics work at once. To avoid confusion, each
display on a machine is assigned a display number
(beginning at 0) when the X server for that display is started. The
display number must always be given in a display name.
-
screen number: Some displays share a single keyboard
and pointer among two or more monitors. Since each monitor has its
own set of windows, each screen is assigned a screen
number (beginning at 0) when the X server for that display is
started. If the screen number is not given, screen 0 will be
used.
On POSIX systems, the default display name is stored in your
DISPLAY environment variable. This
variable is set automatically by the xterm
terminal emulator. However, when you log into another machine on a
network, you might need to set DISPLAY by
hand to point to your display, see
Section 10.4.3.2.
More information can be found in the X man pages.
