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Hydra was designed to be modular and secure, and intended to be flexible enough for easy experimentation. The system was implemented in the programming language
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336:; Cohen, E.; Corwin, W.; Jones, A.; Levin, R.; Pierson, C.; Pollack, F. (June 1974).
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25:
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Reflections in a pool of processors: An experience report on C.mmp/Hydra
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Proceedings of the fifth ACM symposium on operating systems principles
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308:(November 1, 1975). "Policy/mechanism separation in Hydra".
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84:
66:
58:
48:
36:
24:
304:Levin, R.; Cohen, E.; Corwin, W.; Pollack, F.;
184:to run on it. Hydra was created as part of the
1839:
1776:Category: Microkernel-based operating systems
669:
385:
180:designed to support a wide range of possible
8:
250:Computer Structures: Principles and Examples
19:
1846:
1832:
1318:
962:
952:
701:
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662:
654:
392:
378:
370:
18:
219:
7:
1800:
1798:
1885:Microkernel-based operating systems
1875:Carnegie Mellon University software
1818:. You can help Knowledge (XXG) by
365:from the original on July 1, 2007.
342:. Vol. 17. pp. 337–345.
253:. New York, New York: McGraw-Hill.
14:
1890:Object-oriented operating systems
267:Capability-Based Computer Systems
1802:
1780:
1779:
1770:
1769:
1:
247:; Mashburn, Henry M. (1982).
169:) is an early, discontinued,
416:Principle of least privilege
1030:Multi-Environment Real-Time
452:Capability-based addressing
92:; 49 years ago
72:; 53 years ago
1906:
1797:
190:Carnegie Mellon University
31:Carnegie Mellon University
1742:
447:Capability-based security
195:The name is based on the
442:Object-capability model
422:Confused deputy problem
264:Levy, Henry M. (1984).
1865:Operating system stubs
1814:-related article is a
1786:Category: Microkernels
294:(Report). p. 945.
287:; Harbison, Samual P.
199:mythological creature
155:Command-line interface
561:Programming languages
348:10.1145/355616.364017
318:10.1145/800213.806531
1765:Open-source software
1272:Java virtual machine
611:Specialised hardware
312:. pp. 132–140.
237:Siewiorek, Daniel P.
1724:Andrew S. Tanenbaum
226:Wulf 74 pp. 337–345
21:
1870:Capability systems
643:Plessey System 250
1827:
1826:
1795:
1794:
1709:James G. Mitchell
1694:Per Brinch Hansen
1513:
1512:
1348:
1347:
1141:
1140:
837:
836:
754:Mac OS nanokernel
651:
650:
472:Operating systems
427:Ambient authority
401:Object-capability
182:operating systems
160:
159:
1897:
1848:
1841:
1834:
1812:operating-system
1806:
1799:
1783:
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1773:
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1319:
1147:Capability-based
963:
953:
702:
678:
671:
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457:Zooko's triangle
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380:
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366:
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296:
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285:Wulf, William A.
281:
275:
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273:. Digital Press.
272:
261:
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233:
227:
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171:capability-based
105:Marketing target
100:
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53:Capability-based
22:
16:Operating system
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1679:Thomas Bushnell
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432:File descriptor
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241:Bell, C. Gordon
235:
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175:object-oriented
149:
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67:Initial release
17:
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1752:
1750:= discontinued
1743:
1740:
1739:
1737:
1736:
1731:
1726:
1721:
1719:Richard Rashid
1716:
1711:
1706:
1704:Jochen Liedtke
1701:
1696:
1691:
1686:
1684:David Cheriton
1681:
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1438:
1435:Icaros Desktop
1432:
1426:
1414:
1408:
1406:
1399:
1398:
1396:
1381:
1379:
1373:
1372:
1370:
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1361:Classic Mac OS
1357:
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1206:HarmonyOS NEXT
1202:
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991:
984:
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950:
942:
941:
939:
938:
931:
928:TI-RTOS kernel
925:
919:
912:
905:
904:Off++ → Plan B
902:
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638:Intel iAPX 432
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545:HarmonyOS NEXT
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150:user interface
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1729:Avie Tevanian
1727:
1725:
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1720:
1717:
1715:
1712:
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1699:Gernot Heiser
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1298:
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1294:
1290:^ integrates
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1023:
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1002:
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989:
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918:
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903:
901:
900:
896:
893:
890:
888:
887:
883:
878:
875:
874:
872:
871:
867:
865:Little Kernel
864:
861:
860:
856:
853:
852:
848:
845:
844:
840:
839:
830:
829:
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823:
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690:
686:
679:
674:
672:
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660:
659:
656:
644:
641:
639:
636:
634:
633:IBM System/38
631:
629:
626:
624:
623:Cambridge CAP
621:
619:
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388:
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361:
357:
353:
349:
345:
341:
340:
335:
334:Wulf, William
331:
327:
323:
319:
315:
311:
307:
306:Wulf, William
302:
301:
290:
286:
280:
277:
269:
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245:Newell, Allen
242:
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213:
211:
209:
204:
202:
198:
197:ancient Greek
193:
191:
187:
183:
179:
176:
172:
168:
165:(stylized as
164:
156:
153:
151:
145:
142:
139:
136:
132:
129:
126:Compile from
125:
123:Update method
121:
117:
115:
111:
107:
103:
89:
87:
86:Final release
83:
69:
65:
61:
59:Working state
57:
54:
51:
47:
44:
41:
39:
35:
32:
29:
27:
23:
1880:Microkernels
1820:expanding it
1809:
1784:
1774:
1762:
1754:
1749:
1746:
1734:William Wulf
1608:
1602:
1596:
1588:
1575:
1525:
1517:
1504:Workplace OS
1502:
1495:
1491:
1484:AIM alliance
1471:
1389:
1383:
1359:
1352:
1337:
1330:
1299:
1291:
1285:
1279:
1252:
1219:
1204:
1197:
1190:
1178:
1177:
1166:
1160:
1154:
1114:Nucleus RTOS
1099:
1082:
1075:
1063:
1044:
1038:
1034:
1028:
1020:
993:
986:
973:
933:
914:
907:
897:
884:
868:
857:
849:
841:
826:
807:
785:
779:
759:
752:
720:
714:
685:Microkernels
594:File systems
515:
338:
309:
279:
266:
259:
249:
231:
222:
205:
194:
166:
162:
161:
114:Available in
90:Final / 1975
62:Discontinued
1674:Gordon Bell
1564:OpenComRTOS
1461:Singularity
1287:Chorus/Jazz
1210:OpenHarmony
689:nanokernels
188:project at
178:microkernel
141:Microkernel
128:source code
1859:Categories
1666:Developers
1633:Frameworks
1570:Phantom OS
1534:ChibiOS/RT
892:µ-velOSity
886:MicroEmpix
602:Tahoe-LAFS
551:Phantom OS
214:References
38:Written in
1757:Real-time
1714:Ike Nassi
1689:Dan Dodge
1453:Microsoft
1323:Unix-like
1313:Macintosh
1221:HarmonyOS
1108:Integrity
1007:Minix-vmd
967:Unix-like
946:Operating
744:Macintosh
541:HarmonyOS
201:the hydra
192:in 1971.
49:OS family
26:Developer
1540:FreeRTOS
1497:Taligent
1429:Broadway
1423:AspireOS
1293:ChorusOS
1214:Oniro OS
1101:ChorusOS
981:GNU Hurd
935:Vanguard
877:GNU Mach
761:NuKernel
521:iMAX 432
484:Capsicum
462:Petnames
409:Concepts
403:security
360:Archived
326:10524544
108:Research
1747:Italics
1656:TI-RTOS
1604:Harmony
1583:SharpOS
1577:RC 4000
1546:HelenOS
1466:ThreadX
1443:MorphOS
1412:AmigaOS
1391:Symbian
1368:kernel)
1366:PowerPC
1354:Copland
1339:MacMach
1332:MachTen
1093:Partial
1039:Unix-RT
1022:MkLinux
1013:Minix 3
959:support
948:systems
922:RTLinux
916:PowerUP
899:nucleus
697:Kernels
489:Fuchsia
476:kernels
356:8011765
148:Default
118:English
95: (
75: (
1650:Genode
1644:Cosmos
1622:Zephyr
1527:BeRTOS
1519:Amoeba
1315:hosted
1281:JavaOS
1261:Wombat
1254:REX OS
1247:PikeOS
1241:LLinux
1234:kernel
1192:Midori
1173:CapROS
1162:KeyKOS
1156:GNOSIS
1077:UNICOS
1065:Spring
1046:OS2000
995:MeikOS
828:WarpOS
815:ExecSG
746:hosted
708:family
569:Cajita
526:Midori
511:CapROS
503:KeyKOS
499:GNOSIS
494:Genode
437:C-list
418:(PoLP)
354:
324:
135:Kernel
1810:This
1598:Thoth
1552:µC/OS
1473:Verve
1405:-type
1403:Amiga
1377:Psion
1199:NLTSS
1179:Hydra
1120:NuttX
1071:Tinix
1058:Redox
1001:Minix
988:Lites
957:POSIX
843:ADEOS
822:Quark
801:-type
799:Amiga
772:Psion
716:Eumel
584:Joule
579:Joe-E
531:NLTSS
516:Hydra
363:(PDF)
352:S2CID
322:S2CID
292:(PDF)
271:(PDF)
208:BLISS
186:C.mmp
167:HYDRA
163:Hydra
43:BLISS
20:Hydra
1816:stub
1763:° =
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1616:VRTX
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1590:SPIN
1492:Pink
1417:AROS
1385:EPOC
1185:seL4
1168:EROS
1132:RIOT
1084:VSTa
1035:MERT
909:Opus
870:Mach
851:EROS
809:Exec
787:EKA2
781:EKA1
733:OKL4
628:Flex
618:BiiN
536:seL4
507:EROS
137:type
97:1975
77:1971
70:1971
1558:MQX
1126:OSE
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859:K42
344:doi
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