X Atom. An Enhanced X-Windows atom. See also atom.
X resource. In AIXwindows, synonymous with resource.
X resource file. In AIXwindows, an ASCII file that includes the definition of all property values that were specified as Public in the Widget Property Editor. Such files are editable by the end user.
X Server. See server.
X Toolkit. See AIXwindows Toolkit.
X-Windows. A network-transparent windowing system developed by MIT. It is the basis for Enhanced X-Windows. See also X11 client.
X.3. The CCITT recommendation that specifies the service provided to an asynchronous (start/stop) device by a packet assembler/disassembler (PAD).
X11 client. An application that is compatible with version X11 of Enhanced X-Windows. See also X-Windows.
X.21. In data communications, the 21st CCITT recommendation in the X series, defining the connection of data terminal equipment to an X.21 public data network for digital leased and circuit-switched services. In X.25 communications, X.21 is available at the physical level only.
X.21 bis. A CCITT recommendation, defining the use on public data networks of DTEs designed for interface to synchronous V series modems.
X.25. The 25th CCITT recommendation in the X series, defining the interface between data terminal equipment and packet switching data networks.
X.25 adapter. Synonym for X.25 Interface Co-Processor/2.
X.25 Interface Co-Processor/2. The separately orderable adapter card that attaches a system unit to an X.25 packet switching data network. Synonymous with X.25 adapter.
X.25 line. In X.25 communications, the physical link between the DTE and the DCE, and the service subscribed to. See also communications line.
X.25 link. The X.25 line from the X.25 adapter to the network terminating unit. In the X.25 API, a link is equivalent to an X.25 port. See also X.25 port and data link.
X.25 network. A service providing packet-switched data transmission that conforms to Recommendation X.25 adopted by the CCITT.
X.25 port. A device in the /dev directory that corresponds to an X.25 link. See also X.25 link.
X.28. The CCITT recommendation that specifies the user interface between an asynchronous (start/stop) device and a packet assembler/disassembler (PAD).
X.29. The CCITT recommendation that specifies the user interface between a DTE and a remote packet assembler/disassembler (PAD).
X.121. The 121st CCITT recommendation in the X series, defining a convention for the network user address (NUA).
XCOFF. See extended common object file format.
xcomms. The command that provides a menu panel for other X.25 commands (the xmanage, xroute, and xtalk commands).
XDR. See External Data Representation.
XDS. The X/Open Directory Service.
XGSL. See Graphics Support Library.
XID. See exchange identification.
XID Node ID. A field that provides the node ID of the physical unit. This value is the ID that is exchanged with the remote physical unit when a connection is first established during the XID operation.
Xlib. In Enhanced X-Windows, a C language subroutine library that client programs use to interface with the windowing system.
Xlib call. See Xlib.
xmanage. The command that enables system managers to manage X.25 ports.
Xmodem protocol. A communications protocol in which messages are sent in blocks of 128 characters, surrounded by control characters. This protocol also uses the checksum program for error checking. The xmodem protocol can detect data transmission errors and then retransmit the data.
xmonitor. The command that enables system managers to monitor activity on X.25 ports.
xmpeek. A program that allows you to ask any host about the status of its xmservd daemon.
XNS. Xerox Network Systems. The network architecture developed by the Xerox Corporation in the 1970s. The XNS Internet protocol suite is similar to the TCP/IP suite. However, different packet formats and terminology are used.
XOM. X/Open Object Management.
xroute. The command that enables system managers to manage the X.25 routing list.
Xt intrinsics. See intrinsics.
xtalk. The command that enables users to use X.25 to converse with other users, exchange messages and files, and manage X.25 address lists.
XTI. X/Open Transport Interface. A library implementation, as specified by X/OPEN CAE Specification of X/Open Transport Interface and fully conformant to X/OPEN and XPG4 Common Application Environment (CAE) specification, that defines a set of transport-level services that are independent of any specific transport provider's protocol or its framework.
XY format. The format of a pixmap organized as a set of bitmaps representing individual bit planes that appear in most-significant to least-significant bit order. See also Z format.