pristine:0000003797-111bd9843aa6f065c39b415278ba84332de317daf4d9d6c546dcfb5cb7b22bef [Initial tree with system-agnostic rendezvous library. Taylor R Campbell **20090911171730] hash: 0000037819-6badf9af1722add3ee996e44eaf3cbb416143cde8e4ad8c5e81fd5121ba21b1a [Initial tree with Scheme48 port. Taylor R Campbell **20090911172504] hash: 0000041108-fe9f883aba8202d3bc97c44fdb4397249b2a1f4763941ad85f7b025b247bd6f7 [Initial tree with MIT Scheme port. Taylor R Campbell **20090911172623] hash: 0000036753-7de2191bf25192e53b22c9226ba8b5f724a8d7ced199587b9aa6f5c3a35488bc [Add README. Taylor R Campbell **20090911181834] hash: 0000003683-406516aa62a5ce30c7488b9429c570ff3a1e3e5ff3ea1e94dc551415ac8c616d [Mention queues and timer rendezvous in README section on porting. Taylor R Campbell **20090911182252] hash: 0000000542-f09aac8c39420da1f5227d1ce514ebdabef09e44830b92c105cea99b5bd8e679 [Mention SRFI dependencies in README section on porting. Taylor R Campbell **20090911182350] hash: 0000000274-8c379c222af4b714f5836a26a4eb5f66cef19e78f9f3a505d96bd404fc45bedc [Fix pathnames of MIT Scheme source in README section on MIT Scheme. Taylor R Campbell **20090911182746] hash: 0000000532-c1ea3dc8d1b346e4b2cf295b4f0722d7fa23e6eaf4f1b8ef3e2a6a4bc8e0e92e [Clarify usage message of mit-setup.sh. Taylor R Campbell **20090911182929] hash: 0000000493-f9eca1f2dc890347fc6c90764abf4150679f58e54de09f10426cc1934a27d595 [Fix vestigial reference to FILES variable in mit-clean.sh. Taylor R Campbell **20090911183355] hash: 0000000339-b641a5e74745b8cd5be62e8c995757dc8a39861ec0c907a04fe801526eb18b05 [Fix vestiges of s48-optimistic-record.scm in mit-critical-syntax.scm. Taylor R Campbell **20090911184125] hash: 0000000419-5c57b677c8cc90f44ce6b5288d59be7510d1f444ff6a32ca195eabdd594b9125 [Enable MIT Scheme's `critical' atomicity mechanism in mit-setup.sh. Taylor R Campbell **20090911184307] hash: 0000000610-d0e0e48be593dab39851f63d56334232c462742a95375ea687d50769e6d74643 [Expand README's description of MIT Scheme's atomicity mechanisms. Taylor R Campbell **20090911184715] hash: 0000001189-70fd972b55530469502797e961acf1d7d11612a84ed5ce116f569f4670a8964a [Change heading in semaphore.scm to `Concurrent ML for Scheme'. Taylor R Campbell **20090911184742] hash: 0000000215-3eff1b373cec35b2185e385d26dd401d27e00b4cbd202aefb7233095c2e595ca [Clarify Scheme-CML's miscellaneous dependencies in the README. Taylor R Campbell **20090911203440 - Say what procedures return, if they return anything interesting. - Identify LIST-SORT! as the SRFI 32 procedure, not merely as miscellaneous gobbledigook. Remark that this is the only dependency from SRFI 32. ] hash: 0000000827-338a7e2aa15f9d64d14b7f37f6ce56bf272c724a8dd4b3d953aa4c7ee9851ed8 [Lock placeholders before reading their WAITERS-THEN-VALUE field. Taylor R Campbell **20090912022737] hash: 0000000610-af46c347041b219f9171065b5952d108bcd9ab2c0092b619f4f36d44463cddcc [Use new resumption protocol. Taylor R Campbell **20090914022516 Suspensions may not be resumed by a process that has any object locked. For procedures that need to know whether a suspension can be resumed before it can unlock an object, the procedure WITH-SUSPENSION-CLAIMED gives them this information by claiming suspensions so that any other processes trying to use them will spin or block until the suspension has either been resumed or disclaimed. MAYBE-RESUME may no longer be called when any object is locked, and is simply a special case of WITH-SUSPENSION-CLAIMED. Note that only one suspension may be claimed at any one time. This is a limitation that is hard to lift -- and I suspect that it is a limitation intrinsic to CML. I don't know what might require the limitation to be lifted, though. In the process, simplify the implementations of channels, mailboxes, placeholders, and (internal) condition variables. ] hash: 0000011282-0e6a75bbea093ba514eba596258e5535f5645f3d7d89ba70a518318a5d56ae8e [Eliminate MIT Scheme's `critical' atomicity mechanism. Taylor R Campbell **20090914025803 This no longer works with the new suspension protocol. ] hash: 0000008404-82f439b2b741f9b906930ed090ac96e3f6b7318508eee244fd7a6321a0e332a6 [Eliminate Scheme48's `critical' atomicity mechanism. Taylor R Campbell **20090914030312 Also eliminate stubs for a `transaction' atomicity mechanism. Neither of these works with the new suspension protocol. ] hash: 0000009070-94518d1d832094c64437d422010c2f38aa826a292181462a6609c5f9e1acff8a [Update mit-rendezvous.pkg to reflect new suspension protocol. Taylor R Campbell **20090914030433] hash: 0000001159-f42b296b4a1474d4c7f41689d937cfc4947f2b29a4ff0694a1f8bd5eeb669c3d [Update s48-interfaces.scm to reflect new suspension protocol. Taylor R Campbell **20090914030450] hash: 0000001217-7d68faef9f690d1a8dbdc9802a51aa051bc811712a652b67086e47ebbf805ea1 [Implement new suspension protocol in mit-interrupt-suspend.scm. Taylor R Campbell **20090914030519] hash: 0000006101-a2a58eb34781831c5a47115230aa57a9e43c252795b26e64c8ec7446d27953f2 [Implement new suspension protocol in mit-mutex-suspend.scm. Taylor R Campbell **20090914030643] hash: 0000004952-b652ed3ba2b2919a2346a1b138b74496f2b609b6559901c87e21b61b34646f8a [Implement new suspension protocol in s48-interrupt-suspend.scm. Taylor R Campbell **20090914030722] hash: 0000006365-d8f4fc9bee21d06d27c73e432a0ec578bfad9ae31b3d922caa696477cf35a7e4 [Implement new suspension protocol in s48-optimistic-suspend.scm. Taylor R Campbell **20090914030747] hash: 0000007311-6ba93e889c3d10550ab2c48eed7a9a35cfe8bee128d710c719ec9796877baca5 [Implement new suspension protocol in s48-pessimistic-suspend.scm. Taylor R Campbell **20090914030812] hash: 0000005892-d4bd162d6b54d379f0ac5f7801a87485165b0b004a03b8156347e4aab3746000 [Eliminate vestigial POLL-CHANNEL from channel.scm. Taylor R Campbell **20090914175005] hash: 0000000435-1fe81638bface0a197959a6d462445e36cadbb775dc42a3348bd09bb814bca46 [In mit-mutex-syntax.scm, unintern the internal constructor name too. Taylor R Campbell **20090914175155] hash: 0000000718-bd4b4b2f74fb425151b402ef253676bb272868d35333e5eff11b30ce6e3920b1 [Clarify difference between condvars and placeholders in rendezvous.scm. Taylor R Campbell **20090914175416] hash: 0000000399-50ce37dc695864f87ec3c5351b821a24533378eb3679996c851d358e182a0ff6 [Omit needless QUEUE-EMPTY? test in SEMAPHORE-LOOP of semaphore.scm. Taylor R Campbell **20090914175650 We just put an entry on the queue; of course it's not empty. ] hash: 0000000472-5ab1c35bcce279b90444d3713fa656666106a740b328d8e3ed0ba9fac050029d [Tighten order of reads from locked placeholders in placeholder.scm. Taylor R Campbell **20090914181257 This avoids a race in Scheme48's optimistic atomicity, which guarantees only that collections of locked writes happen atomically, not that collections of locked reads happen atomically. ] hash: 0000004195-c1ffd26b6d68975eb3d887b5eeb4bba0f5ed330219649d5a261677792e13cea2 [Tighten order of reads from locked condvars in rendezvous.scm. Taylor R Campbell **20090914181335] hash: 0000001146-02645ca6fe52c106134e23b58b8e2163bed17cbf5fb16acb1ab844ea7b7043fb [Use new primitive suspension protocol in primitive.scm. Taylor R Campbell **20090914181414 Move suspension abstraction into primitive.scm, using a lower-level `suspender' abstraction that is easier to implement, enabling the complexity of suspensions to be implemented only once and isolated. A suspender is an object with a lock and with which a process can suspend until another process resumes it with a value. ] hash: 0000003437-99eabf43cd7fa9279ed68457c79e3d807a12f872ecdb35d035b44daff24d87f5 [Update mit-rendezvous.pkg to reflect new primitive suspenders. Taylor R Campbell **20090914181458] hash: 0000000991-5c0538dc989df969d4d45be7d8a3e509cb83b2acff1fdf20b3150e19d832c5c9 [Implement new primitive suspenders in mit-interrupt-suspend.scm. Taylor R Campbell **20090914181753] hash: 0000007610-e24193f135a00c2fbb4644e5a05f18268bf2ed85f1fc8b44d76f85d1a3339011 [Implement new primitive suspenders in mit-mutex-suspend.scm. Taylor R Campbell **20090914181806] hash: 0000005946-db16f06dac8b5f2de32203d01dc1a8693ac4dced18d4719f1cdd29ffff525df9 [Update Scheme48 configuration to reflect new primitive suspenders. Taylor R Campbell **20090914182124] hash: 0000001433-3c9ae4ce33edcbc2ac7d8973f07a397568b5a84a65b3a8d3e8a9ef5d53ef722a [Implement new primitive suspenders in s48-optimistic-suspend.scm. Taylor R Campbell **20090914182151] hash: 0000010654-198958ceb73365b836528f6c9ac5a669f64c00fb2b5de6ed0f556927e54036e5 [Implement new primitive suspenders in s48-pessimistic-suspend.scm. Taylor R Campbell **20090914182222] hash: 0000007105-f5ef5965e445b0deee1436c4677f7cbf008aa26e552bff5b625706490baea1fa [Implement new primitive suspenders in s48-interrupt-suspend.scm. Taylor R Campbell **20090914182246] hash: 0000008261-81cd8228257eb8c494d4afd8474044e5e0aaff2d5b36227466aa37c899ea7180 [Add srfi-18-record.scm, implementing locked records with SRFI 18. Taylor R Campbell **20090914185009] hash: 0000002706-a4597bb3439ae5e0ef508ab37b7798f73e694d8c35d9b5302d4c04ebc8456119 [Add srfi-18-suspend.scm, implementing suspenders with SRFI 18. Taylor R Campbell **20090914185035] hash: 0000003378-de87436ba8d488e3a446fc4479a16ad5f7d4bff2960e90b19ad4464253d02f13 [Add srfi-18-time.scm, implementing time rendezvous with SRFI 18. Taylor R Campbell **20090914185052] hash: 0000003508-e3c0e82daec66ac451725102bc37f8b1d734c1ab6f59ee0fdbcfb2ab521b0ae3 [Refer to srfi-18-*.scm in the README as prototypical implementations. Taylor R Campbell **20090914185944 Also note that some Scheme systems have broken hygiene, breaking srfi-18-record.scm. ] hash: 0000001277-df1f7a6b7ba7ee6f59428ccf5714a72acde2855fd2ad89403bb9c360ffbaaf77 [In s48-interrupt-suspend.scm, restore interrupts more carefully. Taylor R Campbell **20090914191912 On exit from SUSPENDER/SUSPEND, re-enable the interrupts that were enabled on entry to it, rather than those that BLOCK enabled. Re-enable the ones that BLOCK enabled only while spinning for the suspender's lock. ] hash: 0000002361-c461a90fabaf3ac06de8b8d7f9650c2035df36606d3fef0d4747993d26296312 [Add operation to explicitly abort a suspender. Taylor R Campbell **20090915003156] hash: 0000000182-22e6d10d34b4e510a1b2824cb75c7a93910d5d435e405e1aeaaf8b76e0ae771c [Update s48-interfaces.scm to add SUSPENDER/ABORT. Taylor R Campbell **20090915003304] hash: 0000000269-639bd1da0242340901be3047ce61a95ed230a2e627fa069666ff5a6dbf29ffc9 [Update mit-rendezvous.pkg to add SUSPENDER/ABORT. Taylor R Campbell **20090915003323] hash: 0000000274-539485404dc9252c87e0790439d611b7f61c395a7bead75116ddb1cdfab943fe [Fix bug in SUSPENDER/SUSPEND's spin-lock in s48-interrupt-suspend.scm. Taylor R Campbell **20090915011659] hash: 0000001413-ccc0588e66ca4f6d22c67dd088c4267eefae036deb3cd07d89e18e627e968b3d [Implement SUSPENDER/ABORT in mit-interrupt-suspend.scm. Taylor R Campbell **20090915011824] hash: 0000000529-2f456a58a48eb5152c64a4bc0f5ef06af704b22d58096abc9719a254cbfc60e3 [Implement SUSPENDER/ABORT in mit-mutex-suspend.scm. Taylor R Campbell **20090915011838] hash: 0000000439-ff5f1e85bc630cd7a86b7cb09d15b5f2c85a3a030079cb550307e454950f54a6 [Implement SUSPENDER/ABORT in s48-interrupt-suspend.scm. Taylor R Campbell **20090915011852] hash: 0000000447-b88a3a839157b34339e788b5d6ef6773604f422cd0bdf7b905df454b3659aa34 [Implement SUSPENDER/ABORT in s48-optimistic-suspend.scm. Taylor R Campbell **20090915011947] hash: 0000000449-77bd8b4396d1de54e7d2abd7361e0a6d4fd048556f9130a982dd556e14d2dc39 [Implement SUSPENDER/ABORT in s48-pessimistic-suspend.scm. Taylor R Campbell **20090915011959] hash: 0000000451-a8eb46ed7b201af8003d4cb27a38d37e666319fb154b088a039e5373dbe7f4a3 [Implement SUSPENDER/ABORT in srfi-18-suspend.scm. Taylor R Campbell **20090915012105] hash: 0000000885-7cf3bb97afc2d88381d3c31b71222bb12cb96b1662d6c15fcf17033c15faa563 [Join pages in s48-packages.scm since omitting */{CRITICAL,TRANSACTION}. Taylor R Campbell **20090915012227] hash: 0000000162-62ee9b752acfcaf680510a47631ffeba3be67507c2cf79f36851047117be6cda [Change BLOCK not to loop in s48-interrupt-suspend.scm, and say why. Taylor R Campbell **20090915015014] hash: 0000000929-b4a784234a4f3f8774e4f60ca2296916fb28182209b8fb9fb3df9d1397564ebd [Change BLOCK not to loop in s48-pessimistic-suspend.sccm. Taylor R Campbell **20090915015055] hash: 0000000639-e2e7905d914e352abe0671a657a63a502ed1c4c73efc1f1960ae88d42e3df11c [Add comment to s48-pessimistic-suspend.scm about an atomicity bug. Taylor R Campbell **20090915015127] hash: 0000000391-77d7da41a4e0afc5e46a44ac9c9cdd1e209d375e74cb3dfd0dfac203cc638260 [Add safer reimplementation of queues for Scheme48. Taylor R Campbell **20090915190310] hash: 0000010588-0c1494a29aece8314f89c54bbbb3a5beb9f49f82c3c1a20208655c73046a0621 [Use new queues in Scheme48 RENDEZVOUS-CHANNELS structure. Taylor R Campbell **20090915190323] hash: 0000000300-d410a74fa772ee75c84e09758ace073db5314eadc1dc08659cabe4085e1b312d [Use new queues in Scheme48 RENDEZVOUS-MAILBOXES structure. Taylor R Campbell **20090915190333] hash: 0000000301-10063052c83eb1969c617bf9a6d193acd55030a933f2f6cba736a59591fdcfaa [Use new queues in Scheme48 RENDEZVOUS-SEMAPHORES structure. Taylor R Campbell **20090915190345] hash: 0000000303-e239b7027d8b8fa7773152c3b3db22e951e97fce139704bc111152f2aa04b3c3 [Fix bug in SUSPENDER/SUSPEND's spin-lock in mit-interrupt-suspend.scm. Taylor R Campbell **20090916002515] hash: 0000001852-192dea0fe660f10686b253747a5927f1f15691135def1e047b64a91d412a531b [Fix bug in SUSPENDER/SUSPEND's spin-lock in s48-optimistic-suspend.scm. Taylor R Campbell **20090916191723] hash: 0000001955-470fe4cb393b26bc21b646dc3b83404626675c7ecb3800f690d67ec8782c9eb8 [Fix SUSPENDER/LOCK's provisional effects in s48-optimistic-suspend.scm. Taylor R Campbell **20090916193904] hash: 0000000645-907324fc33da180ac1d25bd7187b0d097bb20d0b47343827e7cc01d8ed86c3f9 [Add queue.scm, a simple and portable implementation of queues. Taylor R Campbell **20090924064354] hash: 0000002601-6ac6c0e693632e16f00f1e3f8a6d8165901ffaf3d9535ffbe227c5f1200f1fd5 [Add sort.scm, implementing Olin Shivers' list merge sort. Taylor R Campbell **20090924064544] hash: 0000015918-f7013a395bcbb833df77bceb0abaec331e55106e7e02730500639ffa3eea70c6 [Initial port to Gambit. Taylor R Campbell **20090924065839 This is still pretty kludgey, because it is not obvious how to persuade Gambit to work with macros, and of course there's nothing resembling a module system. ] hash: 0000011320-ff3ac94744bbfdb321ef5525ec1d59874cfb4151450da258b9a7c7d185ee79d8 [Fix bugs in seldom-used operations in s48-optimistic-queue.scm. Taylor R Campbell **20091225065512 . Change DELETE-FROM-QUEUE! to return true if the object was in the queue and false if it was not, to match Scheme48's definition. . Change LIST->QUEUE to construct a valid queue structure, using the last pair of the list as its back, rather than using the front as its back. . Eliminate LIST->QUEUE! and QUEUE->LIST!, which were neither exposed nor adequately thought through. Thanks, Robert Ransom. ] hash: 0000004359-2334a161e80792d3d2181dc98529ac0b35fd6535e1812051cf9476979ee676ef [Reset a channel's priority when a rendezvous for it is enabled. Taylor R Campbell **20091225074053] hash: 0000000201-c2ef90f59efb4c21191470ef35dea9424a72196cdf9d85a7388891a44910ad3f [Don't say `atomic' when `isolated' is meant in s48-optimistic-queue.scm. Taylor R Campbell **20100711204542 Ignore-this: 6f868c2b87c8d5fc9aa59cd9dbe0454d ] hash: 0000001655-4a55594aabbcde4117261669ba63981a6a9f50d46516375b9e13267226d1d08c [Set -u in mit-clean.sh. Taylor R Campbell **20100712220100 Ignore-this: f3f31d95190237dfe8ce6fdb2c87833f ] hash: 0000000161-99d5c8a2dbf412e5c92feaafc25120ffe157290267c4ddfcdb34b5309be6a57d [Set -u in mit-setup.sh. Taylor R Campbell **20100712220107 Ignore-this: a89ffee4bbb93cab6b15b255ae6ec9f5 ] hash: 0000000168-9fa0d4e296e17b669734c1cc2c48dfc09a114fdd14532d95c30e7ed0e935e358 [Bump copyright year on mit-interrupt-suspend.scm to 2010. Taylor R Campbell **20100712223004 Ignore-this: 50ec77211bb17e33f61ae211b4913e2a ] hash: 0000000292-3b45685f4733bca0674221803289632700cf2247be3248847f1f12f5be7210a9 [Bump copyright year on mit-mutex-suspend.scm to 2010. Taylor R Campbell **20100712223014 Ignore-this: ae755b9eec7764afb5baa8148ac45d68 ] hash: 0000000284-9d775493ad657c8fd8067c9ef58d005b5b051d59584e9b3b9bb3a1825ade43d5 [Bump copyright year on s48-interrupt-suspend.scm to 2010. Taylor R Campbell **20100712223039 Ignore-this: b6124a36438d83b4a48ec4e9ecd0fe84 ] hash: 0000000292-6b8cfff7c3a5b2f6072e92a6f3462ca37936ada8292eab8b8cdb0c745bcf667b [Bump copyright year on s48-optimistic-suspend.scm to 2010. Taylor R Campbell **20100712223101 Ignore-this: 295199157ac0a31576f0376fcd94651a ] hash: 0000000294-5f69d378905fa3de443545d3ced1b1cdd5d7b6377adc6b09114404a61d5c26d6 [Bump copyright year on s48-packages.scm to 2010. Taylor R Campbell **20100712223113 Ignore-this: d8d8976ca2b674f591b30dd3c396708d ] hash: 0000000274-1047eb6159f3ffa373876ff56dab549b9e468d5bd69423707c0692ab476a8680 [Bump copyright year on s48-pessimistic-suspend.scm to 2010. Taylor R Campbell **20100712223133 Ignore-this: b5dec8a0d78a45224c43dc197ee393ab ] hash: 0000000296-7937be7883804ed4b7f25484edc189b64d2795d993d1540ababb2b90c4f66cfc [Bump copyright year on srfi-18-suspend.scm to 2010. Taylor R Campbell **20100712223144 Ignore-this: 675f0848a763b266619d5d57c38bd74c ] hash: 0000000280-04d3c855e3327d7d92f1bafc67edd603cbbb424d15cbfe4912a8db87b88fa14f [Make mit-interrupt-suspend.scm suspender operations safe to interrupt. Taylor R Campbell **20100712223231 Ignore-this: 46e1e542a5e618f359eeaada5b1f2faa ] hash: 0000005083-0a9961b14a67fa009911561775a4e47ebe78048968dd4f0116a3885fcd37208f [Make mit-mutex-suspend.scm suspender operations safe to interrupt. Taylor R Campbell **20100712223348 Ignore-this: d70d88d58ad837801e97a0abb97bb71b ] hash: 0000003654-d1c1b668bb1a66ed80eb324c5df73d09063f0b1fd5d217d7c85abf28824a43dc [Make s48-interrupt-suspend.scm suspender operations safe to interrupt. Taylor R Campbell **20100712223624 Ignore-this: be9543b9b8c13aa31ec411172b8ded68 ] hash: 0000004929-11effba8cac1914a3925334a2a9f3c3450f6cadd2513a672c38975bcb21ea281 [Make s48-optimistic-suspend.scm suspender operations safe to interrupt. Taylor R Campbell **20100712223702 Ignore-this: dcbea1a2c441e2142063173922e8e14b ] hash: 0000006164-13d24b200341f1ac69aca5fce21838830d968c376c11c5e694b01e3e45640c95 [Make s48-pessimistic-suspend.scm suspender operations safe to interrupt. Taylor R Campbell **20100712223730 Ignore-this: d8b84adc3f8be4f2db8ada020e293b2b ] hash: 0000003210-fbfbf52599d5f26255b86e3489695714abafe4a0805af104b792fe3823503ece [Make srfi-18-suspend.scm suspender operations safe to interrupt. Taylor R Campbell **20100712223743 Ignore-this: eb79533343479f30bbbacd83e84f1ef8 ] hash: 0000003794-c61cc5f6438681ec109339e86aa8d2b44b8f805aee5b8817f3da428e61c389cc [Bump copyright year on primitive.scm to 2010. Taylor R Campbell **20100712223756 Ignore-this: 84812613448f631b17066334dbe19d11 ] hash: 0000000268-5acdf3900053e6efffc235bacfdad9c62e6cf6dad74be5d72f6a6a2dfdd9b7d2 [Add comment to primitive.scm about MAYBE-RESUME inside WITH-x-LOCKED. Taylor R Campbell **20100712223804 Ignore-this: 39236baf22851d41f963f1f7f2613840 ] hash: 0000000345-1fd33dbfce3d1cfd8e4b932df059090179875e0138a68e8e31c48dcc17661aca [Bump copyright year on rendezvous-syntax.scm to 2010. Taylor R Campbell **20101009045916 Ignore-this: d0ccd651c0d70774344dab149acfb59b ] hash: 0000000284-f76708f05a3793b893cc38cc0bc6ac5b2e3a0ce802f15cb1628819b449b6029d [Add OR-style clauses to RENDEZVOUS-CASE. Taylor R Campbell **20101009045927 Ignore-this: 1a6b44535789c240f3e9ae73a43e0b24 ] hash: 0000000398-d043d575a00d2f3c7c2a7784372fd72c1294aa4337db3678dd4eb9f7b5a8a43e [Bump copyright year on mit-time.scm to 2010. Taylor R Campbell **20101011153720 Ignore-this: 41ba3c5264f6aca875374629a008047a ] hash: 0000000266-067aedd2750fc43533b2af28a7f11f8fdf15feb40a74d486998fb0c409362156 [Fix mit-time.scm to deregister timer events on nack. Taylor R Campbell **20101011153729 Ignore-this: 1dcb26f1e592e1c36f152405ba2fdb70 ] hash: 0000001552-a8699f7278e5019d9952fb9977a9cf99a3d1124a75abb19e8468e98c0a39b91a