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will return, signaling the presence of data to be read. Suppose, the reader only consumed part of data from the buffer. In level-triggered mode, further calls to
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35:. Its function is to monitor multiple file descriptors to see whether I/O is possible on any of them. It is meant to replace the older
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will return immediately, as long as the pipe's buffer contains data to be read. In edge-triggered mode, however,
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105:(RB-tree) data structure to keep track of all file descriptors that are currently being monitored.
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Controls (configures) which file descriptors are watched by this object, and for which events.
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argument denoting the configurable kernel object, against which they cooperatively operate.
51:, to achieve better performance in more demanding applications, where the number of watched
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for a scalable I/O event notification mechanism, first introduced in version 2.5.45 of the
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was added in version 2.6.2 of the Linux kernel mainline, released in
February 2004.
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had mistakes that could have been avoided, had it learned from its predecessors:
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parameter allows epoll behavior to be modified. It has only one valid value,
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and is deprecated as of Linux kernel version 2.6.27 and glibc version 2.9.
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Linux-specific system call for a scalable I/O event notification mechanism
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388:. However, a large part of his criticism was addressed by
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is large (unlike the older system calls, which operate in
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will return only once new data is written to the pipe.
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will return only when a new event is enqueued with the
490:"Using epoll() For Asynchronous Network Programming"
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408:was added in version 4.5, released in March 2016.
295:/file descriptors to be monitored. In most case,
275:Waits for any of the events registered for with
532:(Second ed.). O’Reilly. pp. 97, 98.
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338:will return as long as the condition holds.
139:object and returns its file descriptor. The
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605:"Ubuntu Slaughters Kittens | BSD Now 103"
326:modes. In edge-triggered mode, a call to
1909:Free and open-source software portal
1467:Earliest eligible virtual deadline first
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334:object, while in level-triggered mode,
7:
625:"Epoll is fundamentally broken 1/2"
575:"epoll_wait(2) — Linux manual page"
299:is set to the value of the size of
89:, in that it consists of a set of
14:
511:"The Implementation of epoll (1)"
1915:
1914:
1902:
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756:Supported computer architectures
418:
786:The Linux Programming Interface
627:. idea.popcount.org. 2017-02-20
488:Oleksiy Kovyrin (2006-04-13).
468:"epoll(7) - Linux manual page"
217:can be ADD, MODIFY or DELETE.
1:
378:input/output completion ports
349:has received data, a call to
434:Input/output completion port
1969:
1628:High-performance computing
1450:Process and I/O schedulers
305:struct epoll_event *events
1882:
1461:Completely Fair Scheduler
726:Tanenbaum–Torvalds debate
291:is the maximum number of
93:functions, each taking a
1382:Kernel same-page merging
530:Linux System Programming
219:
157:
112:
1725:OS-level virtualization
554:"epoll_wait: maxevents"
151:is an older variant of
1870:List of Linux adopters
812:Linux User Group (LUG)
470:. Man7.org. 2012-04-17
1948:Linux kernel features
528:Love, Robert (2013).
1456:Brain Fuck Scheduler
716:Linux Mark Institute
1650:Real-time computing
922:Linux Standard Base
341:For instance, if a
1943:Events (computing)
1638:Compute Node Linux
1224:C standard library
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856:Linux kernel oops
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802:Linux conferences
539:978-1-449-33953-1
517:. September 2014.
372:pointed out that
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1488:SCHED_DEADLINE
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1483:O(1) scheduler
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643:External links
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406:EPOLLEXCLUSIVE
398:EPOLLEXCLUSIVE
384:(Solaris) and
370:Bryan Cantrill
366:
363:
320:edge-triggered
318:provides both
312:
309:
220:
158:
149:epoll_create()
113:
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103:red–black tree
79:is similar to
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649:epoll manpage
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556:. Jun 3, 2010
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492:. Kovyrin.net
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145:EPOLL_CLOEXEC
118:epoll_create1
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82:
74:
72:
64:
60:
59:
54:
50:
43:
38:
34:
30:
27:
23:
1953:System calls
1919:
1900:
1886:
1616:Linux kernel
1534:Tomoyo Linux
1129:File systems
1012:
784:
736:SCO disputes
697:Organization
690:Linux kernel
629:. Retrieved
619:
608:
596:Ghostarchive
594:Archived at
590:
579:. Retrieved
577:. 2023-03-30
569:
558:. Retrieved
548:
529:
523:
514:
505:
494:. Retrieved
483:
472:. Retrieved
426:Linux portal
402:EPOLLONESHOT
394:EPOLLONESHOT
368:
340:
314:
274:
212:
134:
75:
70:
69:operates in
62:
57:
49:system calls
33:Linux kernel
26:Linux kernel
19:
18:
1621:Linux-libre
1514:Exec Shield
1393:Framebuffer
1096:Video4Linux
953:System Call
781:Developers
721:Linus's law
654:epoll patch
382:event ports
293:epoll_event
243:epoll_event
199:epoll_event
135:Creates an
73:(1) time).
29:system call
1937:Categories
1708:Hypervisor
1670:PREEMPT_RT
1575:KernelCare
1563:Raw device
1493:SCHED_FIFO
1403:KMS driver
1320:Components
1175:securityfs
1061:Crypto API
1003:Linux-only
889:System.map
792:kernel.org
751:menuconfig
746:GNU GPL v2
631:2017-10-06
581:2023-07-06
560:2023-07-06
496:2014-03-01
474:2014-03-01
451:References
359:epoll_wait
355:epoll_wait
351:epoll_wait
336:epoll_wait
328:epoll_wait
303:argument (
225:epoll_wait
91:user-space
1847:LYME-LYCE
1570:initramfs
1539:Linux PAM
1408:Netfilter
1278:libcgroup
1244:libhybris
1216:libraries
1164:hugetlbfs
1115:Userspace
1048:In-kernel
1033:readahead
955:Interface
904:initramfs
861:SystemTap
834:Debugging
827:Technical
766:Criticism
515:idndx.com
400:options.
297:maxevents
289:maxevents
287:at once.
285:maxevents
277:epoll_ctl
258:maxevents
163:epoll_ctl
41:select(2)
1921:Category
1863:Adopters
1838:Server:
1819:Embedded
1795:Adoption
1688:PSXLinux
1611:Mainline
1604:Variants
1556:graphics
1509:AppArmor
1498:SCHED_RR
1418:nftables
1362:dm-crypt
1357:dm-cache
1303:liburing
1293:libevdev
1251:dietlibc
1140:configfs
1066:io uring
598:and the
445:libevent
412:See also
307:array).
283:, up to
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1854:Devices
1814:Desktop
1775:coLinux
1770:MkLinux
1755:L4Linux
1683:ÎĽClinux
1665:Xenomai
1655:RTLinux
1595:Ksplice
1524:SELinux
1519:seccomp
1469:(EEVDF)
1413:Netlink
1342:Console
1337:cgroups
1288:libalsa
1214:Wrapper
1192:systemd
1155:debugfs
1124:Daemons
1086:New API
1028:inotify
1023:dnotify
927:x32 ABI
884:vmlinux
876:Startup
775:Support
610:YouTube
301:*events
267:timeout
101:uses a
81:FreeBSD
46:poll(2)
1824:Gaming
1806:of use
1760:ELinOS
1751:Other
1745:OpenVZ
1735:Lguest
1679:-less
1590:kpatch
1585:kGraft
1551:802.11
1347:bcache
1298:libusb
1283:libdrm
1271:Newlib
1256:EGLIBC
1239:Bionic
1234:uClibc
1204:Kmscon
1178:sockfs
1171:procfs
1167:pipefs
1150:devpts
1076:kernfs
1018:splice
973:select
945:Kernel
899:initrd
894:dracut
846:ftrace
808:Users
741:Linaro
704:Kernel
536:
440:kqueue
436:(IOCP)
386:kqueue
281:events
249:events
240:struct
196:struct
86:kqueue
1804:Range
1643:SLURM
1580:kexec
1529:Smack
1463:(CFS)
1443:zswap
1384:(KSM)
1377:evdev
1332:BlueZ
1261:klibc
1229:glibc
1187:tmpfs
1182:sysfs
1145:devfs
1136:bpffs
1013:epoll
1008:futex
988:close
968:ioctl
963:POSIX
851:kdump
390:epoll
374:epoll
347:epoll
332:epoll
316:epoll
205:event
141:flags
137:epoll
127:flags
99:epoll
77:epoll
67:epoll
37:POSIX
24:is a
21:epoll
1842:LAMP
1832:LTSP
1660:RTAI
1438:zram
1433:SLUB
1428:perf
1372:EDAC
1266:musl
1197:udev
1160:FUSE
1056:ALSA
993:sync
983:read
978:open
937:APIs
914:ABIs
841:CRIU
797:LKML
534:ISBN
396:and
365:Bugs
343:pipe
322:and
234:epfd
172:epfd
44:and
1740:LXC
1718:Xen
1713:KVM
1677:MMU
1633:INK
1398:LVM
1388:LIO
1367:DRM
1101:IIO
1091:RCU
1071:DRM
866:BPF
731:Tux
392:'s
264:int
255:int
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