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info.cern.ch. 30.5 X Window System
The X Window System, or just X, is a client-server application that lets multiple clients
(applications) use the bit-mapped display managed by a server. "The server is the software
that manages a display, keyboard, and mouse. The client is an application program that runs
on either the same host as the server or on a different host. In the latter case the common
form of communication between the client and server is TCP, although other protocols such
as DECNET can be used. In some instances the server is a dedicated piece of hardware (an
X terminal) that communicates with clients on other hosts. In another instance, a stand-alone
workstation, the client and server are on the same host and communicate using interprocess
communication on that host, without any network involvement at all. Between these two
extremes is a workstation that supports clients on the same host and clients on other hosts.
X requires a reliable, bidirectional stream protocol, such as TCP. (X was not designed for an
unreliable protocol such as UDP.) The communication between the client and server consists file:///D|/Documents%20and%20Settings/bigini/Documenti/homenet2run/tcpip/tcp-ip-illustrated/other.htm (6 of 11) [12/09/2001 14.47.58] Chapter 30. Other TCP/IP Applications of 8-bit bytes exchanged across this connection. [Nye 1992] gives the format of the more
than 150 messages exchanged between the client and server across their TCP connection.
On a Unix system, when the X client and X server are on the same host, the Unix domain
protocols are normally used instead of TCP, because there is less protocol processing than if
TCP were used. The Unix domain protocols are a form of interprocess communication that
can be used between clients and servers on the same host. Recall in Figure 2.4 that when
TCP is used for communication between two processes on the same host, the loopback of
this data t...
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This test prep was uploaded on 04/04/2014 for the course ECE EL5373 taught by Professor Guoyang during the Spring '12 term at NYU Poly.
- Spring '12