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describes his own personal daemon to be something like the modern concept of a moral conscience: "The favour of the gods has given me a marvelous gift, which has never left me since my childhood. It is a voice that, when it makes itself heard, deters me from what I am about to do and never urges me
251:
a child process and then immediately exiting, thus causing init to adopt the child process, or by the init process directly launching the daemon. In addition, a daemon launched by forking and exiting typically must perform other operations, such as dissociating the process from any controlling
570:
If the daemon wants to ensure that it will not acquire a new controlling tty even by accident (which happens when a session leader without a controlling tty opens a free tty), it may fork and exit again. This means that it is no longer a session leader in the new session, and cannot acquire a
333:. This is an egregious misunderstanding. "Daemon" is actually a much older form of "demon"; daemons have no particular bias towards good or evil, but rather serve to help define a person's character or personality. The
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process (process number 1) as its parent process and has no controlling terminal. However, more generally, a daemon may be any background process, whether a child of the init process or not.
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perform the functions of daemons. They run as processes, usually do not interact with the monitor, keyboard, and mouse, and may be launched by the operating system at boot time. In
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that helped to sort molecules, stating, "We fancifully began to use the word daemon to describe background processes that worked tirelessly to perform system chores".
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However, any
Windows application can perform the role of a daemon, not just a service, and some Windows daemons have the option of running as a normal process.
345:
A further characterization of the mythological symbolism is that a daemon is something that is not visible yet is always present and working its will. In the
541:(in the parent "half" of the fork). This allows daemon's parent (shell or startup process) to receive exit notification and continue its normal execution.
218:, for clarification that the process is in fact a daemon, and for differentiation between a daemon and a normal computer program. For example,
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In a strictly technical sense, a Unix-like system process is a daemon when its parent process terminates and the daemon is assigned the
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is the state of being helped or protected by a kindly spirit. As a rule, UNIX systems seem to be infested with both daemons and demons.
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214:, rather than being under the direct control of an interactive user. Traditionally, the process names of a daemon end with the letter
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time that will respond to network requests, hardware activity, or other programs by performing some task. Daemons such as
761:: regular applications that ran in the background. To the user, these were still described as regular system extensions.
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605:, and other operating system calls to provide their own permission masks and not to depend on the umask of the caller.
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system, uses daemons but uses the term "services" to designate software that performs functions selected from the
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On a Unix-like system, the common method for a process to become a daemon, when the process is started from the
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systems inherited this terminology. Maxwell's demon is consistent with Greek mythology's interpretation of a
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and later versions, Windows services are configured and manually started and stopped using the
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256:(tty). Such procedures are often implemented in various convenience routines such as
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Many people equate the word "daemon" with the word "demon", implying some kind of
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Detaching from the invoking session, usually accomplished by a single operation,
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In the general sense, daemon is an older form of the word "demon", from the
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so that the process does not keep any directory in use that may be on a
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Creating a new session and becoming the session leader of that session.
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757:. Later versions of classic Mac OS augmented these with fully fledged
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After the term was adopted for computer use, it was rationalized as a
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448:(used in Windows, from Windows NT onwards, and later also in Linux),
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in 1963, his team was the first to use the term daemon, inspired by
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In modern usage in the context of computer software, the word
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Optionally removing unnecessary variables from environment.
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Daemons that connect to a computer network are examples of
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is used, particularly for daemons that operate as part of
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process. A daemon is usually created either by a process
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is a daemon that implements system logging facility, and
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environment, daemon-like programs were implemented as
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271:may also perform defined tasks at scheduled times.
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27:Computer program that runs as a background process
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30:For spirit in Classical Greek mythology, see
8:
929:"sshd: OpenSSH server process | SSH Academy"
670:and "multi-threaded" datagram servers under
907:"Glossary of z/OS terms and abbreviations"
590:file system (allowing it to be unmounted).
279:The term was coined by the programmers at
243:of a daemon is often, but not always, the
91:Learn how and when to remove this message
34:. For broader coverage of the topic, see
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834:
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54:This article includes a list of general
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7:
688:terminate-and-stay-resident programs
514:or from a startup script such as an
321:states the following about daemons:
295:, an imaginary agent in physics and
464:). Sometimes the more general term
316:Unix System Administration Handbook
18:Operating system service management
551:Dissociating from the controlling
60:it lacks sufficient corresponding
25:
786:List of computer term etymologies
228:is a daemon that serves incoming
759:faceless background applications
483:for Disk And Execution MONitor.
403:
369:
329:connection between UNIX and the
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156:
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872:"The Origin of the word Daemon"
640:If the process is started by a
263:Systems often start daemons at
1052:Unix Daemon Server Programming
1:
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1058: (archived 2019-10-30)
29:
702:systems, programs called
114:that are daemons include
741:Classic Mac OS and macOS
716:Service Control Manager
75:more precise citations.
438:Alternative terms for
343:
139:
474:client-server systems
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791:List of Unix daemons
700:Microsoft Windows NT
112:desktop environments
1077:Servers (computing)
1072:Process (computing)
953:"Daemon Definition"
612:0, 1 and 2 for the
285:Fernando J. Corbató
107:Components of some
917:. 31 January 2006.
734:scripting system.
522:script, involves:
212:background process
140:
36:Server (computing)
1029:. freedesktop.org
1027:"systemd.service"
983:System Manager's
911:IBM Documentation
751:system extensions
666:and specified as
584:working directory
582:) as the current
499:Unix-like systems
281:MIT's Project MAC
239:environment, the
148:operating systems
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16:(Redirected from
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314:δαίμων. In the
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890:. Retrieved
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855:. Retrieved
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801:Software bot
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708:Windows 2000
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668:Type=forking
642:super-server
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608:Redirecting
574:Setting the
518:script or a
512:command line
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144:multitasking
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933:www.ssh.com
811:Web service
561:Becoming a
289:Project MAC
275:Terminology
73:introducing
1066:Categories
1033:August 25,
938:2023-12-04
892:2008-11-15
857:2008-10-22
823:References
806:User space
732:PowerShell
694:Windows NT
339:eudaemonia
331:underworld
319:Evi Nemeth
128:PulseAudio
56:references
724:net start
630:/dev/null
481:backronym
458:ghost job
260:in Unix.
258:daemon(3)
146:computer
81:June 2018
975:inetd(8)
846:"daemon"
779:See also
728:net stop
546:setsid()
357:Socrates
254:terminal
124:unetwork
1054:at the
981:FreeBSD
745:On the
690:(TSR).
682:In the
664:systemd
659:systemd
653:launchd
634:logfile
603:creat()
588:mounted
565:leader.
539:exiting
535:forking
456:), and
445:service
348:Theages
327:satanic
249:forking
221:syslogd
206:) is a
134:), and
69:improve
1012:Manual
1004:Darwin
985:Manual
678:MS-DOS
626:stderr
622:stdout
599:open()
466:server
440:daemon
365:daemon
305:daemon
152:daemon
132:usound
58:, but
32:Daimon
1008:macOS
765:macOS
672:inetd
656:, or
647:inetd
632:or a
628:) to
618:stdin
595:umask
460:(XDS
452:(IBM
360:on".
353:Plato
312:Greek
235:In a
136:Avahi
116:D-Bus
109:Linux
1035:2012
1006:and
769:Unix
753:and
726:and
624:and
537:and
516:init
505:init
454:z/OS
442:are
432:-mən
398:-mən
301:Unix
269:cron
265:boot
245:init
237:Unix
226:sshd
150:, a
915:IBM
698:On
553:tty
533:by
468:or
462:UTS
430:DAY
401:or
396:DEE
230:SSH
180:or
142:In
126:),
1068::
1018:^
965:^
955:.
931:.
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831:^
720:sc
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