function is used to open a connection to an X server.
&key :display :protocol
Specifies the name of the host machine on which the
server executes. A string must be acceptable as a host,
but otherwise the possible types are not constrained and will
likely be very system dependent.
An integer that specifies which display device on the
host should be used for this connection. This is needed
since multiple displays can be controlled by a single X
server. The default is display 0 (zero).
A keyword argument that specifies which network protocol
should be used for connecting to the server (for example,
:tcp, :dna, or :chaos). The set of
possible values and the default value are implementation specific.
that serves as the connection to the X server and contains all
the information about that X server.
Authorization, if any, is assumed to come from the environment.
After a successful call to
all screens on the display can be used by the client