Unnumbered Acknowledgement [95]

User Agent (MHS, OSI) [95]

UnternehmensAnwendungsArchitektur (IM) [95]

User Agent Accessibility Guidelines (WAI) [95]

Unix Appletalk Bridge (Apple, AppleTalk, Unix) [95]

Universal Access Control (IBM) [95]

Uniform Automatic Data Processing System [95]

Universal Asymmetric Digital Subscriber Line (DSL, ADSL) [95]

The Ubiquitous Amiga Emulator: Base UAE is a 100% software Amiga (500) hardware emulator. This is the base package including all support files and the most common binary of UAE for X. NOTE: For "proper" use of UAE, you need some version of the Kickstart ROM, and some OS running on top of this (most likely some version of the Amiga OS). Both don't comply to the DFSG (to say the least) and must be obtained from other sources. There is information in the package docs how to obtain these if you are owner of an Amiga box. However, there is a minimal free build-in Kickstart replacement, and at least some demo disks are reported to run with it. [3]

Unknown / Unrecoverable Application Error (Windows) [95]

The Ubiquitous Amiga Emulator: Exotic binaries UAE is a 100% software Amiga (500) hardware emulator. This package contains binaries of UAE with "exotic" display modes. [3]

The Ubiquitous Amiga Emulator: Suid root binaries UAE is a 100% software Amiga (500) hardware emulator. This package contains binaries of UAE with display modes that require root privileges (i.e. SVGA and X-DGA versions). These binaries are often considered to be a little bit faster, however this very much depends on your hardware. I (and the upstream authors) DON'T RECOMMEND INSTALLING THESE BINARIES (for the usual security problems) unless you have good reasons for it. [3]

User Authorization File [95]

User Agent Protocol Data Unit (PDU) [95]

Universal Asynchronous Receive and Transmit [95]

UnAvailable Seconds (DS1/E1, DS3/E3) [95]

Universal ADSL Working Group (Org, ADSL, DSL) [95]

UniBus Adapter (DEC) [95]

Unsolicited Bulk Email (spam, Internet, UCE) [95]

Download and decode Usenet binaries UBH (Usenet Binary Harvester) is a Perl console application which automatically discovers, downloads, and decodes single- and multi-part Usenet binaries. UBH provides searching via Perl regular expression and a pre-selection capability whereby the user can interactively choose which binaries to download. [3]

Ungermann-Bass Network Interface [95]

Unspecified Bit Rate (ATM, CBR, VBR, ABR, QOS) [95]

Universal Code (Internet, DOMAIN) [95]

a dialect of lisp using turtle graphics famous for teaching kids. This is the UC Berkeley implementation of logo written primarily by Daniel Van Blerkom, Brian Harvey, Michael Katz, and Douglas Orleans. This version of logo is featured in Brian Harvey's book _Computer_Science_Logo_Style, _Volume_1: _Symbolic_Computing_ (ISBN 0-262-58151-5). This version provides the following special features: - Random-access arrays. - Variable number of inputs to user-defined procedures. - Mutators for list structure (dangerous). - Pause on error, and other improvements to error handling. - Comments and continuation lines; formatting is preserved when procedure definitions are saved or edited. - Terrapin-style tokenization (e.g., [2+3] is a list with one member) but LCSI-style syntax (no special forms except TO). The best of both worlds. - First-class instruction and expression templates. - Macros. [3]

Uniform Commercial Code [95]

Unsolicited Commercial E-mail (Usenet, spam, UBE) [95]

Update Configuration File - preserve user changes in config files Debian policy states that configuration files must preserve user changes during package upgrade. The easy way to achieve this behavior is to make the configuration file a 'conffile', in which case dpkg handles the file specially during upgrades, prompting the user as needed. This is appropriate only if it is possible to distribute a default version that will work for most installations, although some system administrators may choose to modify it. This implies that the default version will be part of the package distribution, and must not be modified by the maintainer scripts during installation (or at any other time). This script attempts to provide conffile like handling for files that can not be labelled conffiles, are not shipped in a Debian package, but handled by the postinst instead. This script allows one to maintain files in /etc, preserving user changes and in general offering the same facilities while upgrading that dpkg normally provides for "conffiles". Additionally, this script provides facilities for transitioning a file that had not been provided conffile like protection to come under this schema, and attempts to minimize questions asked at install time. Indeed, the transitioning facility is better than the one offered by dpkg while transitioning a file from a non-conffile to conffile status. [3]

User-Computer Interface [95]

University of California at Los Angeles (org., USA) [95]

UCLA Virtual Machine (OS, UCLA, VM), "UCLA VM" [95]

A compiler wrapper for uClibc This package includes utilities that function as a toolchain for compiling with uClibc instead of the native libc. The utilities have names such as powerpc-uclibc-gcc (depending on the architecture), and should behave identically to the base utilities, except that they use headers and libraries provided in the libuclibc-dev package. Most utilities are symbolic links to the correct underlying utility, although gcc and ld are implemented as wrapper binaries that call gcc and ld with the necessary arguments and command line options. [3]

uClibcLinux is a Linux distribution based on uClibc. This source-based distribution has two main goals: - provide an easily extensible build-system - provide a repository of software compiling and running with uClibc. Initial version 0.4.5 was released June, 25, 2002. [33]

The Linux/Microcontroller project is a port of Linux to systems without a Memory Management Unit (MMU). Pronounced "you-see-linux", the name uClinux comes from combining the greek letter "mu" and the english capital "C". "Mu" stands for "micro", and the "C" is for "controller". uClinux was first ported to the Motorola MC68328: DragonBall Integrated Microprocessor. The first target system to successfully boot is the 3Com PalmPilot using a TRG SuperPilot Board with a custom boot-loader created specifically for our Linux/PalmPilot port. Version 20020701 was initially released on Freshmeat on July 16, 2002. Version 2.4.20-uc0 was released December 4, 2002. Version 2.5.69-uc0 was released May 5, 2003. Version 20030522 was released May 24, 2003. [33]

Universal Computer Protocol (SMS, Europe) [95]

Under Color Removal (DTP) [95]

Universal Classification System [95]

Universal [multiple-octet] coded Character Set (ISO, IEC, DIS 10646, Unicode) [95]

generate BDF fonts containing subsets of ISO 10646-1 codepoints [34]

University of California at Santa Barbara (org. USA) [95]

University California San Diego (org., USA) [95]

Connection proxy for UCSPI tools This package contains a proxy program that passes data back and forth between two connections set up by a UCSPI server and a UCSPI client. See http://cr.yp.to/proto/ucspi.txt for more information on UCSPI. See http://em.ca/~bruceg/ucspi-proxy/ for recent informations. [3]

UNIX-domain socket client-server command-line tools unixclient and unixserver are command-line tools for building UNIX domain client-server applications. unixclient connects to a UNIX domain socket and runs a program of your choice. unixserver creates a UNIX domain socket, waits for incoming connections and, for each connection, runs a program of your choice. unixclient and unixserver conform to UCSPI, the UNIX Client-Server Program Interface, using UNIX domain sockets. UCSPI tools are available for several different networks. See http://cr.yp.to/proto/ucspi.txt for more information on UCSPI. See http://em.ca/~bruceg/ucspi-unix/ for recent informations. [3]

Uptime Daemon UD runs in the background constantly checking the current uptime against your 3 best uptime records. If the current uptime surpasses a record, that becomes the new record. By using a template UD can create HTML files that shows the current uptime records. The HTML files are updated by the daemon. [3]

Universal DataBase [server] (IBM, DB) [95]

Universal Decimal Classification [95]

Universal Description, Discovery and Integration of business for the web (org., WWW) [95]

The Unix Desktop Environment UDE is more then just another windows manager. Designed to compensate for the shortcomings of many other similar packages, UDE features many innovative improvements. The project does not use any special GUI-Libraries such as Qt or GTK+ and is based on the standard Xlibs (also to make UDE faster) UDE - get used to it. [3]

Universal Disc Format (CD, OSTA) [95]

User Defined Function [95]

Tools for UDF filesystems and DVD/CD-R(W) drives This package contains a number of user-space tools related to creating filesystems in the UDF (Universal Disk Format), which is primarily used for DVDs, but sometimes also CD-ROMs: mkudffs - Format a device, creating an empty UDF filesystem cdrwtool - Low-level drive management (e.g. set writing speed, format) pktsetup - Set up a packet writing device (/dev/pktcdvd0) for a drive Note that you need Linux 2.4 or later to mount UDF filesystems. The kernel patches that accompany these tools are not currently packaged for Debian, but are being merged into the 2.4 kernel tree. [3]

very small DHCP client This is the very small DHCP client written by Moreton Bay/Lineo. [3]

very small DHCP server This is the very small DHCP server written by Moreton Bay/Lineo. [3]

UmweltDatenKatalog (NUIS-SH) [95]

??? [hardware description language] (HDL), "UDL/I" [95]

Ultra Direct Memory Access (DMA, ATA) [95]

Ultra-DMA - an advanced technology which provides for even faster throughput, up to 33.3 MB/s in UDMA mode 2 and 66.7 MB/s in UDMA mode 4, twice to four times that of EIDE, for much lower prices than SCSI. [32]

User Defined Objects [95]

see User Datagram Protocol (UDP). [94]

Usenet Death Penalty (Usenet, spam) [95]

User Datagram Protocol (Internet, RFC 768) [95]

User Datagram Protocol - a simple connectionless TCP service. [32]

One of the protocols for data transfer that is part of the TCP/IP suite of protocols. UDP is a "stateless" protocol in that UDP makes no provision for acknowledgement of packets received. See also: Packet Switching, TCP/IP. [5]

UDP is a transport protocol that provides "datagram" services on top of IP. Contrast: There are two transport protocols: UDP and TCP. Both of these are responsible for hooking up the programs that are communicating with each other, whereas the underlying IP is simply responsible for getting the packets from machine to machine across the Internet. UDP is essentially just a light-weight version of TCP. Whereas TCP will automatically retransmit lost packets, UDP doesn't care. This is actually a benefit for audio/visual, but a severe disadvantage when transferring files. There is nothing to exciting about UDP. The source port identifies the application on the sending machine. The destination port identifies who is to receive the data. The length indicates how much data is in the packet; the checksum verifies that it has not been accidentally altered in transit (though it cannot protect against deliberate alteration). [96]

User Datagram Protocol / Internet Protocol, "UDP/IP" [95]

Uniform [DOMAIN name] Dispute Resolution Policy (ICANN) [95]

Universal Digital Subscriber Line [95]

User-defined DataType (DB) [95]

Universal Data Voice Multiplexer [95]

Ultra Enhanced Integrated Drive Electronics (IDE, HDD) [95]

User End of Volume [95]

Universal File System [95]

Unix File System (Unix) [95]

Universal Font Scaling Technology (Agfa) [95]

NFS UID mapping daemon. This package contains the UID mapping daemon (rpc.ugidd) which is used on NFS clients to do UID/GID mapping. [3]

Ultra High Aperture [ratio] (LCD, TNLCD) [95]

United Hitech Corporation (manufacturer, Taiwan) [95]

Universal Host Controller Interface (USB, Intel, VIA, OHCI) [95]

Ultra High Frequency [95]

User Head Label [95]

UHU-Linux is a Linux distribution from Hungary. It is an easily installable, dpkg-based distribution, with fully automatic hardware detection (based partly on Mandrake and other distros). It is primarily aimed at beginners. Version 1.0 was released April 18, 2003. [33]

Unix International (manufacturer, Unix) [95]

User Interface [95]

allows you to change certain Gnome user interface. [34]

Qt ui compiler This package contains the Qt ui compiler. It is needed to build more and more Qt based applications. There are 2 versions of this binary, one with KDE widget support and one without. This one is compiled without. [3]

User Identification Code [95]

Expands to the user ID of the current user, initialized at shell startup. [40]

see user identification (UID). [94]

the User ID number of the user that owns this process. [32]

Unit IDentifier (cryptography, EES) [95]

User IDentification [95]

Unique ID Listing (POP3, RFC 1939) [95]

User Interface Language [95]

User Interface Management System [95]

Universal Identification Number (ICQ) [95]

UmweltInformationsSystem [95]

Micro In-System Programmer for Atmel's AVR MCUs This utility is required to program AVR chips with object code created by the ava assembler/linker. It supports in-system programming, Atmel's prototype board/programmer, and an extremely low-cost parallel port programmer. [3]

User Interface System Reference Model [95]

United Kingdom Education and Research Networking Association (org., UK) [95]

United Kingdom Office for Library and information Networking (org.) [95]

do underlining [34]

Uncommitted Logic Array [95]

Unified Local Area Network Architecture [95]

University of London Computer Center (org., UK) [95]

The Userspace Logging Daemon ulogd is a daemon that listens for Netlink packets generated by iptables's ULOG target. Basically, it's a replacement for syslog for logging packets, and does a much better job - it logs to files, mySQL, and soon will be able to log remotely. mySQL support is in a separate package, called ulogd-mysql. The relevant kernel support is included in a patch - kernel-patch-ulog. ulogd homepage: http://www.gnumonks.org/projects/ulogd [3]

mySQL extension to ulogd This extension adds mySQL support to ulogd; please see ulogd's description. description. [3]

Upper Layer Protocols (FC) [95]

User Location Interface [95]

Ultra Large Scale Integration [95]

UltraLinux is one of the first, if not the first, port of Linux to the SPARC family of processors most commonly found in Sun workstations and clones. It supports most workstations including the older 32bit SPARC processors and the newer 64bit UltraSPARC based workstations. [33]

A GGI based presentation tool UltraPoint is a simple, XML based presentation program designed to help aid with instant preparation. (This does not measn 'easy to use this program') As compared with most of the existing tools, UltraPoint requires no special adjustment cost (e.g. positions of objects). -- Features . Drawing with GGI (General Graphics Interface) . Accessing a lot of font formats with VFlib 3.6. . Arranging scaled images with ImageMagick. [3]

Ultra Low Voltage [95]

Unified Memory Architecture [95]

Universal Measurement Architecture (Unix, X/Open) [95]

Upper Memory Area (Intel) [95]

Universal Measurement Architecture Data Storage (UMA) [95]

Upper Memory Block (Intel, UMA) [95]

UMB Scheme is a public domain implementation of the Scheme programming language. Scheme is a statically scoped and properly tail-recursive dialect of the Lisp programming language, designed with clear and simple semantics and a minimal number of ways to form expressions. Install the umb-scheme package if you need an implementation of the Scheme programming language. [4]

United Microelectronics Corporation (manufacturer) [95]

UNI Management Entity (UNI, ILMI) [95]

Set of routines for solving unsymmetric sparse linear systems. UMFPACK is a set of routines for solving unsymmetric sparse linear systems, Ax=b, using the Unsymmetric MultiFrontal method. Written in ANSI/ISO C, with a Matlab (Version 6.0 and later) interface. The new code is faster than V2.2.1, uses dynamic memory allocation, and has a symbolic preordering and analysis phase that also reports the upper bounds on the nonzeros in L and U, flop count, and memory usage in the numeric phase. It includes a Matlab interface. V3.2 is for double-precision matrices only (not complex). [3]

Unified Method Language (CASE) [95]

Unified Modelling Language (OOP) [95]

User-mode Linux (utility programs) User-mode Linux is a port of the Linux kernel to its own system call interface. It provides a kind of virtual machine, which runs Linux as a user process under another Linux kernel. This is useful for kernel development, sandboxing, jailing, experimentation, and many other things. This package contains userspace utilities for use with User-mode Linux, including uml_mconsole, uml_moo, uml_switch, uml_net and tunctl. [3]

Installer and viewer for .umod-files (Unreal Mod files) UmodPack is a crossplatform tool for umod installation and unpacking. umod files are packages containing files with setup instructions for an Unreal mod (modification). For more information on Unreal mods in general see <http://www.planetunreal.com/modcentral/> [3]

unmount file systems [34]

Unified Messaging System [95]

This is the distribution of the UMSDOS file system utilities. With the kernel configured accordingly these utilities allow the usage of of Unix filesystem feature on top of the MSDOS filesystem. It is even possible to run Linux completely on an MSDOS formatted disk without repartitioning or reformatting. [3]

Universal Mobile Telecommunications System (IN, mobile-systems) [95]

n. Used to refer to the Unix operating system (a trademark of AT&T, then of Novell, then of Univel, then of the Open Group; the source code parted company with it after Novell and was owned by SCO, which was acquired by Caldera) in writing, but avoiding the need for the ugly (TM) typography. Also used to refer to any or all varieties of Unixoid operating systems. Ironically, lawyers now say that the requirement for the trademark postfix has no legal force, but the asterisk usage is entrenched anyhow. It has been suggested that there may be a psychological connection to practice in certain religions (especially Judaism) in which the name of the deity is never written out in full, e.g., 'YHWH' or 'G-d' is used. See also glob and splat out. [7]

Universal Network Architecture [95]

Replace accented letters by their unaccented equivalent read data from stdin, replace accented letters by their unaccented equivalent and write the result on stdout. [3]

A UNIX command that returns a description of the current operating system. It describes the machine hardware type (e.g. Pentium), the name of the node on the network, which release of the OS, the OS name, specific CPU information, and the version of the OS. Key point: This is often the first command a hacker will run on the system when the hacker breaks in remotely. Hackers rarely known exactly what kind of system they have attacked. The other popular command hackers might execute is id. Example: Running uname -a on one of my systems results in: Linux gandalf.robertgraham.com 2.2.13-4mdk #1 Tue Sep 7 18:23:11 CEST 1999 i686 unknown [96]

get name and information about current kernel [34]

print system information [34]

UNsolicited Address Resolution Protocol (ARP, RFC 1868) [95]

Universal Naming Convention (IBM, MS, Novell, LAN) [95]

UNiform rules of Conduct for Interchange of Trade data by teletransmission (EDIFACT) [95]

Unix Net for Computer security in Law Enforcement (org., USA, Unix), "U.N.C.L.E." [95]

hides the mouse in X after a period of inactivity unclutter is a program which runs permanently in the background of an X session. It checks on the X mouse pointer position every few seconds, and when it finds it has not moved (and no buttons are pressed on the mouse, and the cursor is not in the root window) it hides the mouse cursor. It restores the mouse cursor when the mouse is moved or when a mouse button is hit. [3]

compress or expand files [34]

United Nations EDIFACT (ISO 9735, EDIFACT), "UN/EDIFACT" [95]

convert spaces to tabs [34]

United Nations Guidelines for Trade Data Interchange (UN/EDIFACT, predecessor), "UN/GTDI" [95]

Removing the markup tags from a HTML file This program removes all HTML tags from a HTML file and directs it's output to stdout. It can be used as a filter for getting the text content of a HTML file without the need of firing up a web browser. [3]

Universal Network Interface (Cogent) [95]

User Network Interface [95]

a type of communication between hosts (or computers) on a network where a host talks directly to another computer. See broadcast and multicast. [32]

The international character set. The United States characters ASCII only needs 7-bits to encode text. There are fewer than 100 characters in the English language (26-upper-case, 26-lower-case, 10-digits, and a bunch of punctuation). Since 7-bits has 128 combinations, it is sufficient to cover the characerts plus a few control codes. However, there are other alphabets, such as Russian, Greek, and Hebrew. Even worse, far-eastern languages like Chinese, Japanese, and Korean use symbols/ideographs to represent words without a strict alphabet. The Unicode character set was built to represent all these characters within a 2-byte (16-bit) format. Roughly 30,000 characters from all the popular languages have been assigned in an internationally agreed upon format. Key point: Most computers are built to handle 1-byte characters, and do not like the idea of handling 2-bytes for each character. Therefore, a multi-byte character set has been designed to store Unicode. It is called "UTF8". It is the native character set for many newer systems, such as Java. Using "multibyte" rather than "fixed" character set means that a variable number of bytes can be used, depending upon how many bytes/bits are needed to represent the character. The key issue here is that every 7-bit ASCII character can be encoded in all forms. For example, older Microsoft IIS web-servers would check for backtracking attacks. However, a UTF8 encoding of the backtracks would bypass the IIS checks, but would still be passed to the filesystem. Encoding Bits Encoding of '.' 0xxxxxxx 7-bits 2E 110xxxxx 10xxxxxx 11-bits C0 AE 1110xxxx 10xxxxxx 10xxxxxx 15-bits E0 80 AE See also: encoding [96]

put the console in Unicode mode. [34]

put the console out of unicode mode (ie. in 8-bit mode). [34]

Chinese Input Method Libaray General Chinese Input method interface and API. It is using by chinput and unicon now. [3]

X11 dual-width GNU unicode font The GNU unicode font is an X11 bitmap font in iso10646 encoding. It is useful if you have X programs such as the yudit text editor that are unicode aware. [3]

A tring of characters that identifies an Internet resource, including the type of resource and its location. There are two types of URIs: Uniform Resource Locators (URLs) and Relative URKS (REL URQ). [39]

A publicly routable address for resources transmitted via the World Wide Web (WWW). URLs can be name-based (such as www.example.com) or address-based (such as 192.168.1.2). [94]

One of two basic kinds of Universal Resource Identifiers (URI), a string of characters that precisely identifies an Internet resource's type and location. For example, the following fictitious URL identifies a World Wide Web document.

http://www.wolverine.virglnia.edu/~toros/winerefs/merlot.html

Where http://, indicates the domain name of the computer on which it is stored. www.wolverine. virginia .eau, fully describes the document's location within the directory structure ~toros/winerefs/), and includes the document name and extension merlot.html. [39]

A battery that can supply continuous power to a computer system in the event of a power failure. The battery, charged while your computer is swtiched on, kicks in if the power fails and provides power for 10 minutes or more, during which time you can save fils and shut down the computer to preserve the integrity of crucial data. [39]

A battery that can supply continuous power to a computer system in the event of a power failure. The battery charged while your computer is switched on, kicks in if the power fails and provides power for 10 minutes or more, during which time you can save files and shut down the computer to preserve the integrity of crucial data. [39]

remove duplicate lines from a sorted file [34]

A file-synchronization tool for Unix and Windows Unison is a file-synchronization tool for Unix and Windows, written in OCaml. It allows two replicas of a collection of files and directories to be stored on different hosts (or different disks on the same host), modified separately, and then brought up to date by propagating the changes in each replica to the other. Unison offers several advantages over various synchronization methods such as CVS, Coda, rsync, Intellisync, etc. Unison can run on and synchronize between Windows and many UNIX platforms. Unison requires no root privileges, system access or kernel changes to function. Unison can synchronize changes to files and directories in both directions, on the same machine, or across a network using ssh or a direct socket connection. Transfers are optimised using a version of the rsync protocol, making it ideal for slower links. Unison has a clear and precise specification, and is resilient to failure due to its careful handling of the replicas and its private structures. [3]

A file-synchronization tool for Unix and Windows - GTK interface This package adds the optional GTK interface to the file synchronization tool 'unison'. [3]

Ubiquitous aNd Integrated Teamwork Environment (SIT) [95]

converts between different systems of units. GNU 'units' program converts quantities expressed in various scales to their equivalents in other scales. The 'units' program can only handle multiplicative scale changes. For example, it cannot convert Celsius to Fahrenheit but it can convert temperature differences between those temperature scales. [3]

UNIVersal Automatic Computer [95]

The mean solar time of the meridian of Greenwich, England, used as the basis for calculating standard time throughout the world. [94]

/yoo'niks/ n. [In the authors' words, "A weak pun on Multics"; very early on it was 'UNICS'] (also 'UNIX') An interactive time-sharing system invented in 1969 by Ken Thompson after Bell Labs left the Multics project, originally so he could play games on his scavenged PDP-7. Dennis Ritchie, the inventor of C, is considered a co-author of the system. The turning point in Unix's history came when it was reimplemented almost entirely in C during 1972-1974, making it the first source-portable OS. Unix subsequently underwent mutations and expansions at the hands of many different people, resulting in a uniquely flexible and developer-friendly environment. By 1991, Unix had become the most widely used multiuser general-purpose operating system in the world - and since 1996 the variiant called Linux has been at the cutting edge of the open source movement. Many people consider the success of Unix the most important victory yet of hackerdom over industry opposition (but see Unix weenie and Unix conspiracy for an opposing point of view). See Version 7, BSD, USG Unix, Linux. Some people are confused over whether this word is appropriately 'UNIX' or 'Unix'; both forms are common, and used interchangeably. Dennis Ritchie says that the 'UNIX' spelling originally happened in CACM's 1974 paper "The UNIX Time-Sharing System" because "we had a new typesetter and troff had just been invented and we were intoxicated by being able to produce small caps." Later, dmr tried to get the spelling changed to 'Unix' in a couple of Bell Labs papers, on the grounds that the word is not acronymic. He failed, and eventually (his words) "wimped out" on the issue. So, while the trademark today is 'UNIX', both capitalizations are grounded in ancient usage; the Jargon File uses 'Unix' in deference to dmr's wishes. [7]

A computer operating system (the basic software running on a computer, underneath things like word processors and spreadsheets). Unix is designed to be used by many people at the same time (it is multi-user) and has TCP/IP built-in. It is the most common operating system for servers on the Internet. Apple computers' Macintosh operating system, as of version 10, is based on Unix. [5]

A computer operating system commonly used on the Internet. Uplink: The communication link from the transmitting earth station to the satellite. [44]

An operating system used on a wide variety of computers, from mainframes to personal computers, that supports multitasking and is ideally suited to multiuser applications. UNIX is a very flexible operating system, well-suited to the needs of advanced computer users. With more than 200 commands, inadequate error messages, and a cryptic command syntax, however, UNIX imposes heavy burdens on occasional users and the technically unsophisticated. With the development of UNIX shells such as NeXTStep, the operating system may play a much wider role in computing. Because Bell Laboratories was prohibited from marketing UNIX by the antitrust regulations governing AT&T before the 1980s, UNIX was provided without charge to colleges and universities throughout North America. beginning in 1976. In 1979, the University of California at Berkeley developed a popular version of UNIX for VAX computers. In the early 1980S, AT&T gained the right to market the system and released System V in 1983. See Berkeley UNIX System V lnterface Definition (SVID) and Linux, Wide Area Information Server (WAIS). [39]

Key point: There really is no "UNIX", but just various implementations designed along the same guidelines. Different versions of UNIX are more or less related, and there is extensive cross-germination of ideas, so that something good that appears in one will eventually migrate to others. Contrast: There have been two main branches of UNIX: SVR4 (System V Release 4) and BSD (Berkeley Standard Distribution). Many security issues depend upon which base the system was derived. Example: Sun Solaris, IBM AIX, SCO, SGI Irix, Apple A/UX, BSD, HP/UX. Key point: UNIX is case-sensitive, whereas Windows and Macintosh are "case-insensitive" but "case-preserving". Windows has a compatibility mode that allows case-sensitivity, which can sometimes be exploited with other techniques in order to compromise the system. Key point: The BSD branch has spawned many open-source variants, such as FreeBSD and OpenBSD. OpenBSD is considered one of the more secure versions of UNIX. Security experts spend the most time on OpenBSD in order to clean up bugs like buffer-overflows. However, in 1999, the dramatic rise of hacking and publication of bugs has led to a heightened awareness of these problems, which may lead to other systems becoming equally scoured for bugs. How to: In order to harden UNIX, you generally do the following: Always start from a fresh machine newly installed. When installing, do not install any options that aren't absolutely necessary. Many people are unsure if an option is needed, so they install it just to be sure. Do the opposite (don't install it in order to make sure you don't introduce a backdoor). After installation, remove all unnecessary software; anything with an X Windows GUI is a good start. Cleanse /etc/inetd.conf of all unnecessary services. For any server connected to the Internet, pretty much everything in there will be unnecessary. Install a Tripwire-style package to detect when system files have changed (i.e. binaries in /sbin and configuration files in /etc). This doesn't secure the system, but it helps in detecting when intrusions have occurred. Note that this program is difficult to get running and maintain over the long term. Install TCP Wrappers to log connections and provide some limited access control. Shadow /etc/passwd. Remove all entries for disabled services and set a dummy shell for those accounts that shouldn't have shell access. Redirect syslog to a secure system or drop-box. Get rid of Telnet, use ssh. Plan to do all remote administration and file copies through ssh. If you are extremely paranoid, put binaries on a CD-ROM. Some versions of open source UNIXes can even boot from CD-ROMs. Install packet filtering software. Install network intrusion detection software. Key point: Typical UNIX weaknesses are: default passwords weak (guessable, crackable) passwords NIS misconfigurations NFS holes incorrect permissions race conditions (esp. in /tmp) exploitable SUID programs sendmail problems UPS (Uninterruptible Power Supply) [2] A UPS continues to provide electricity to equipment in the case of a power failure. Much of security contains flawed policies for fail-open/fail-close. By causing devices to fail (such as cutting their power), an intruder may be provided access. For example, electronic doors will automatically open in cases of power failures in order to prevent people from getting trapped. Likewise, some firewalls are configured with bypasses that will allow access in cases of power failure to the firewall. Key point: The MTBF of the average UPS is five to ten years. High-end colos attempt to provide power grids that exceed this. Key point: Increasingly, UPS units are being given interfaces for network management. This allows them to be hacked and have their power interrupted. [96]

Pronounced "you-niks," a multi-user, multitasking network operating system developed at Bell Labs in the early 1970s. Linux is based on, and is highly compatible with, UNIX. [94]

UNIX began as a proprietary operating system developed by Bell Laboratories in the 1960s. It eventually spawned a number of mutually incompatible commercial versions from such companies as Apple (Mac OS X), Digital (Digital UNIX), Hewlett-Packard (HPUX), IBM (AIX.), NeXT (NeXTSTEP) and others. [8]

UNIX is an operating system commonly used on Workstations, and multi-user larger systems. It is a very powerful operating system for administering many users, multi-tasking and communications and has played a major role in the development of the Internet - it is the preferred operating system for host Internet connections (World Wide Web, email servers, and specialist hardware such as routers). [2]

A network, based on long-distance telephone uploads and downloads. UUCP allows UNIX users to exchange files, electronic mail and Usenet articles. In the 1980s, when Internet connectivity was hard to come by, UUCP played an important role in providing support for the UNIX operating system. [39]

A utility that converts plain text files in UNIX format to DOS format. [93]

Shared library for Morse programs Package needed by unixcw, cwcp and xcwcp. It contains a shared library with Morse code functions. [3]

ODBC tools libraries Binaries and libraries from the unixODBC package. COMPONENTS: libodbc.so (ODBC Driver Manager) libodbctxt.so (driver for Text files) dltest (simple cmd line tool) isql (cmd line tool... batch & interactive SQL) Driver Template (a template for Driver programmers) [3]

Qt-based GUI ODBC tools Qt-based GUI Binaries from the unixODBC package. ODBCConfig (GUI Setup using libodbcinst.so) DataManager (GUI to explore ODBC Data Sources) [3]

check the password of the invoking user [34]

delete a name and possibly the file it refers to [34]

unlink a file [34]

Unified Network Management Architecture [95]

RTF to other formats converter UnRTF is a moderately complicated converter from RTF to other formats, including HTML, LaTeX, text, and PostScript. Converting to HTML, it supports tables, fonts, colors, embedded images, hyperlinks, paragraph alignment among other things. All other conversions are "alpha"--just begun. [3]

unpack a shar file [34]

United Nations Standard Message, (UN/EDIFACT) [95]

squeeze a sorted word list unsq - unsqueeze a sorted word list [34]

United Nations Trade Data Elements Directory (EDIFACT) [95]

United Nations Trade Data Interchange Directory (EDIFACT) [95]

Remove LaTeX commands from input. Remove LaTeX commands from input and send it to output. [3]

remove trigraphs from C source code [34]

De-archiver for .zip files InfoZIP's unzip program. With the exception of multi-volume archives (ie, .ZIP files that are split across several disks using PKZIP's /& option), this can handle any file produced either by PKZIP, or the corresponding InfoZIP zip program. This version supports encryption. [3]

list, test and extract compressed files in a ZIP archive [34]

The unzip utility is used to list, test, or extract files from a zip archive. Zip archives are commonly found on MS-DOS systems. The zip utility, included in the zip package, creates zip archives. Zip and unzip are both compatible with archives created by PKWARE(R)'s PKZIPfor MS-DOS, but the programs' options and default behaviors do differ in some respects. [93]

Legacy package for unzip-crypt that you should remove. This package exists only to provide a smooth upgrade from the old unzip-crypt to the new unzip. Please remove it. [3]

self-extracting stub for prepending to ZIP archives [34]

uOS is a complete source based Operating System that can be configured and built in a flexible way. uOS was first used in November 2002. It is very new and there are lots of kinks to work out. Although the goal is to make uOS usable by everyeone it currently requires Unix expertise to install and to run. uOS is based on GCC 3.2 / GLIBC 2.3 / WOLK Linux Kernel / X 4.2.1. It supports the newest drivers as well as the newest compilers. Core components are available under the 4F Licensing system (compliant to DFSG and OSI guidelines for Free Software). Initial version 0.81 was released November 6, 2002. [33]

Uni Processor [system] [95]

The Red Hat Update Agent that automatically queries the Red Hat Network servers and determines which packages need to be updated on your machine. [93]

Ultra Port Architecture (Sun, SMP) [95]

User Primary Access Method (BS2000) [95]

Universal Product Code (EAN) [95]

Usage Parameter Control (UNI, ATM) [95]

UserParameterDaten (DDBAC) [95]

daemon to periodically flush filesystem buffers. The update daemon flushes the filesystem buffers at regular intervals. This version does not spawn a bdflush daemon, as this is now done by the kernel's kupdate thread. This package is not needed with Linux 2.2.8 and above. If you do not plan to run a 2.0.x series kernel on this system, you can safely remove this package. update may still be useful in sync mode (as opposed to flush mode) on more recent kernels for the extra paranoid. [3]

maintain symbolic links determining default commands [34]

create or update entry in SGML catalog file [34]

System to update configuration files for clusters automatically A management system to maintain a systemwide template configuration, update-cluster allows for uniform configuration of several cluster-oriented software. NOTE: Using this package may result in automatically overwriting important configuration files. Be careful. [3]

System to update configuration files for clusters automatically A management system to maintain a systemwide template configuration, update-cluster allows for uniform configuration of several cluster-oriented software. This is a module used to configure /etc/hosts using update-cluster infrastructure. [3]

compile fonts.alias files [34]

compile fonts.dir files [34]

compile fonts.scale files [34]

create, remove, enable or disable entry in /etc/inetd.conf [34]

Bash script to select a new ispell default dictionary. [34]

generate Debian menu system [34]

create or update MIME information [34]

(re)generate /etc/modules.conf and /etc/chandev.conf [34]

safely update /etc/passwd, /etc/shadow and /etc/group [34]

install and remove System-V style init script links [34]

program to generate xpdf's configuration file [34]

update a file name database [34]

see user private group (UPG). [94]

To replace older hardware or software with a new or revised version. [94]

User Program Language [95]

Transferring data (usually a file) from a the computer you are using to another computer. The opposite of download. [5]

Umdrehungen Pro Minute (HDD) [95]

User Profile Management (IBM) [95]

Umgekehrte Polnische Notation [95]

Universal Plug 'N Play (PNP), "UPnP" [95]

Universal Procedure Pointer (AE, Apple) [95]

Universal Portable Protocol Stack / Support (Schneider & Koch) [95]

A CGI script to show the world your highest uptimes This CGI script shows your highest uptimes from the uptimed database. [3]

Uninterruptible Power Supply [95]

Unix Print Services (Unix) [95]

UPS Monitor Program Upsd is a UPS monitor program. It supports both local monitoring of a UPS that is directly connected to the computer's serial port and remote monitoring over a network. Remote monitoring is done by polling the master upsd (the one with the direct serial connection to the UPS). There are a number of options to control the poll interval and the delay before shutdown. [3]

Universal Personal Telecommunications (IN) [95]

Universelle Personengebundene Telekommunikation (IN) [95]

Tell how long the system has been running. [34]

Gnome applet that displays your system uptime. Just a small gnome applet which displays how long your system has been running. It is made for use with gnome panel. [3]

Utility to track your highest uptimes Uptimed allows you to track your highest uptimes via boot IDs. Features: - Console program to display statistics - Can send mail if a milestone or a new record is reached [3]

an efficient live-compressor for executables UPX is an advanced executable file compressor. UPX will typically reduce the file size of programs and DLLs by around 50%-70%, thus reducing disk space, network load times, download times etc. The current version can compress executables for DOS, Linux/ELF (i386 only!) and some other files for different OS. NOTE: This package is based on the UCL library, which is licensed under GPL. [3]

Offline mail and news package creator (NNTP version). Uqwk is a program which collects all of a user's unread mail or news and formats it into a packet for offline reading. QWK, Simple Offline Usenet Packet (SOUP), and ZipNews packet formats are supported. Uqwk also accepts reply packets, so replies can be mailed or posted, depending whether the message is marked private (email) or public (news). Uqwk also supports a small offline command language, so the contents of the user's .newsrc file can be viewed and manipulated offline. This version accesses newsgroups via NNTP. [3]

Offline mail and news package creator (spool version). Uqwk is a program which collects all of a user's unread mail or news and formats it into a packet for offline reading. QWK, Simple Offline Usenet Packet (SOUP), and ZipNews packet formats are supported. Uqwk also accepts reply packets, so replies can be mailed or posted, depending whether the message is marked private (email) or public (news). Uqwk also supports a small offline command language, so the contents of the user's .newsrc file can be viewed and manipulated offline. This version accesses newsgroups via a local news spool. [3]

Uniform Resource Agent (WWW) [95]

USB Request Block (USB) [95]

Uniform Resource Citation (WWW) [95]

Uniform Resources Characteristics (URI, WWW) [95]

Universal Resource Identifier (WWW, RFC 1630) [95]

A Uniform Resource Locator is basically the address of any resource on the Internet. You type the URL in your browser and you are whizzed off to the appropriate site. e.g. http://ole.net/ole/ [44]

An acronym for Uniform Resource Locator, URL's are a standardized format for giving a pointer to information available from... A Primer explaining the use of URL's is available. [42]

Uniform Resource Locator (WWW, RFC 1738) [95]

Uniform Resource Locator: a standardized format for giving a pointer to information available from gopher,WWW, finger and other servers. [32]

A problem exists when people need to send binary data as part of a URL. Therefore, URLs include the ability to "encode" binary information as part of the text field. Key point: This encoding mechanism can be used to alter the signature of a hacker attack via web-based protocols. Such encoding can be used to evade detection by lightweight intrusion detection systems that are unable to "normalize" the URL. Example: The Microsoft web-server in their ASP server-side scripts such that a hacker could append a dot to the end of the URL in order to read the script contents rather than executing the script. Microsoft created a patch, but hackers soon found they could evade the patch by URL-encoding the dot (appending a %2E to the end of the scrip rather than a dot). Examples: http://www.robertgraham.com/sample.asp Normal URL http://www.robertgraham.com/sample.asp. Attempt to read script rather than executing it. http://www.robertgraham.com/sample.asp%2E URL-encoding in order to evade patch. http://www.robertgraham.com/sample.%61sp%2E Further URL-encoding in order to evade intrusion detection systems. [96]

determine which browser is responsible for various types of URLs. [34]

utility for squid to perform url redirection. This utility can be used with squid to perform url redirection. It has a structured configuration system which allows greater control over url redirection. [3]

Extracts URLs from text This utility is used to extract URL from text files, especially from mail messages in order to launch some browser to view them. This used to be a part of mutt but has now become an independent tool. [3]

Uniform Resource Name (WWW, RFC 1737) [95]

urpmi takes care of dependencies between rpms, using a pool (or pools) of rpms. You can compare rpm vs. urpmi with insmod vs. modprobe [4]

Unique Resource Serial Number (URI, WWW) [95]

Free, good quality versions of the 35 standard PostScript(TM) fonts, donated under the GPL by URW++ Design and Development GmbH. The fonts.dir file font names match the original Adobe names of the fonts (e.g., Times, Helvetica, etc.). Install the urw-fonts package if you need free versions of standard PostScript fonts. [4]

Unit Separator (BTX, VPCE) [95]

United Software Association (org., USA) [95]

US Advisory Council on the National Information Infrastructure (org., USA) [95]

Universal Synchronous Asynchronous Receiver / Transmitter (IC) [95]

Universal Serial Bus (Intel, USB) [95]

Universal Serial Bus Driver Development Kit (USB, DDK), "USB-DDK" [95]

User-Mode daemon which loads/unloads USB kernel modules When USB devices connect into or disconnect from a USB hub, the usbmgr works as the following according to configuration. a) Loads and unloads files Linux kernel modules. b) Execute file to setup USB devices. usbmgr is available under linux kernel have "/proc/bus/usb". [3]

USB console utilities This applications show what the device tree of the USB bus looks like. It shows a graphical representation of the devices that are currently plugged in, showing the topology of the USB bus. It also displays information on each individual device on the bus. More information can be found at the Linux USB web site http://www.linux-usb.org/ . [3]

usbutils contains a utility for inspecting devices connected to the USB bus. It requires a Linux kernel version 2.3.15 or newer (supporting the'/proc/bus/usb' interface). [4]

USB device viewer USBView is a small GTK application to show what the device tree of the USB bus looks like. It shows a graphical representation of the devices that are currently plugged in, showing the topology of the USB bus. It also displays information on each individual device on the bus. More information can be found at the usbview web site http://www.kroah.com/linux-usb/ . [3]

Unicos Station Call Processor [protocol] (Cray, MPP) [95]

User's Supplementary Documents (BSD, Unix) [95]

Universal Switched Data Capability [consortium] (LCD, org.) [95]

United States Digital Network [95]

User-based SECurity [model] (SNMP) [95]

A world-wide system of discussion groups, with comments passed among hundreds of thousands of machines. Not all USENET machines are on the Internet. USENET is completely decentralized, with over 10,000 discussion areas, called newsgroups. [5]

Point: The protocol for transporting USENET messages is called NNTP: "Network News Transport Protocol". Key point: The USENET Death Penalty (http://www.stopspam.org/usenet/faqs/udp.html) is often applied to NNTP servers in order to stop the flood of spam. It is often applied to ISPs who allow users to send lots of spam or allow their servers to be hijacked. For this reasons, many ISPs (especially high-speed cable modem and DSL providers will scan their customers looking for unauthorized NNTP servers. Controversy: USENET presents a philosophical challenge to the Internet because of its distributed nature. It allows anonymous publishing of material that cannot be traced back to the source. This challenges the historic concepts of intellectual property and how it can be protected. For example, when RC2 and RC4 were posted to USENET, they stopped being trade-secrets. [96]

The leading distributed bulletin board, widely available on UNIX-based computer systems, and linked through the Internet and other computer networks. Offering more than 1,500 new