sisttam samayam

computer sciencilum computer prograamingilum, sisttam time ennathu oru computer sisttathinte kaalakramathekkurichulla ashayathe prathinidheekarikkunnu. eee ardhathil, "samayam" ennathil kalandarile divasangal kadannupokunnathum ulppedunnu.
yugam" ennu vilikkappedunna chila ekapaksheeyamaaya arambha theeyathi muthal sambhavicha "tikkukalude" ennathinte lalithamaaya ennamaayi saadhaaranayaayi nadappilaakkunna oru "sisttam clock" aanu sisttam samayam alakkunnathu. udaaharanathinu, unix, posics-kamplayint sisttangal sisttam samayathe ("unix samayam") 1970 januvari 1 nuu unix yugathinte arambham muthal kazhinja secondukalude ennamaayi encode cheiyunnu. windos 9x, windos enty thudangiya windos epiaiyude 32-bitt, 64-bitt pathippukal nadappilaakkunna sisttangal, oru varsham/maasam/divasam/manikkoor/minitt/second/millisecond moolyamaayi prathinidheekarikkunna sisttam samayam nalkunnu, koodaathe 1601 januvari 1 muthal 100-nanosecond tikkukalude ennathinte ennamaayi prathinidheekarikkunnu.
sisttam samayam kalandar samayamakki maattaan kazhiyum, ithu manushyante graahyathinu kooduthal anuyojyamaaya oru roopamaanu. udaaharanathinu, unix sisttam samayam "yugathinte thudakkam muthalulla sekkantukal" kalandar samayamaayi vivarthanam cheiyunnu "9 septambar 2001 01:46:40 UT". atharam parivartthanangal kaikaaryam cheiyunna library subruitiinukal samaya mekhalakal, delight saving time (dii. ezz. tii), leap secondukal, upayokthaavinte locale krameekaranangal ennivaykkulla krameekaranangalum kaikaaryam cheythekkaam. kalandar samayangale sisttam samayangalayi parivartthanam cheiyunna library dinacharyakalum saadhaaranayaayi nalkunnundu.
nilavil sisttam times 32-bitt poornnasankhya moolyangalaayi sambharikkunna niravadhi nadappaakkalukal varaanirikkunna varsham 2038 prashnam anubhavikkum. eee samaya moolyangal avayude sisttam samaya yugam avasaanichathinusesham overflo ("bittukal theernnu") aakukayum ithu software, hardware pishakukalilekku nayikkukayum cheyyum. 2000-leeii prashnam pariharikkunnathin aavashyamaaya shramangalkk samanamaaya eathenkilum tharatthilulla pariharam eee samvidaanangalkku aavasyamaanu. 32-bitt moolyangalaayi sambharichirikkunna sisttam timestambukal adangiyirikkunna nilavilulla dattaa phayal formaattukalkku ithu valare valia prasnamaayirikkum.
mattu samaya alavukal.
sisttam samayavumaayi adutha bandhamullah "prosess samayam" aanu, ithu oru executing prakriya upayogikkunna motham cpu samayathinte ennamaanu. yathaakramam user code sisttam kernel code execute cheiyunnathinu chelavazhikkunna samayathe prathinidheekarikkunna "user", "sisttam" cpu samayangalayi ithine vibhajikkaam. cpu nirddeshangalo clock cycleukaloo ulla oru koottamaanu prosess time, saadhaaranayaayi mathil samayavumaayi nerittu bandhamilla.
oro fayalukaludeyum directoryudeyum phayal kantrol blockil (allengil inode) timestambukal sambharichukondu fayalukal srishtikkunnathum parishkkarikkunnathum koodaathe/allengil axus cheiyunnathumaaya samayangalude track phayal sisttangal sookshikkunnu.
charithram.
aadya thalamurayile mikka pezhsanal computerukalum theeyathikalum samayangalum track cheythirunnilla. sii. pii/emm operating sisttam pravarthippikkunna samvidaanangalum apple II, bbc micro, comodore pettu ennivayude aadyakaala modalukalum ithil ulppedunnu. oonn-board baattari bakkapulla thalsamaya clock chippukal ulppedunna aadu-oonn peripheral boardukal ibm pisic eksttinum labhyamaayirunnu, ennaal motherboardil nirmmicha theeyathi/samayam hardware sajjeekarichirikkunna vyaapakamaayi labhyamaya aadyathe pisiyaan ibm ettu. computer nettvarkkukalude vyapakamaaya labhyathaykk munbu, sisttam samayam tracucheyyunna mikka pezhsanal computer sisttangalum praadeshika samayavumaayi bandhappett maathrame angane cheythirunnulloo, koodaathe vyathyastha samaya mekhalakalkku alavansukal nalkiyirunnilla.
nilavile saankethikavidya upayogichu, mikka aadhunika computerukalum praadeshika sivil samayathinte track sookshikkunnu, athupole thanne mattu pala gaarhika, vyakthigatha upakaranangalaya vcrs, dvrs, cable tivi reseaverukal, pdas, pejarukal, sell phoneukal, phaaks mesheenukal, telephone uthara mesheenukal, camerakal, camcorderukal, central airconditionerukal, microwave ovanukal ennivayum.
ulchertha sisttangalil (raspberry paii, ardvino, mattu samanamaaya sisttangal enniva polullava) pravartthikkunna microcontrolerukalkku ellaayppozhum samayathinte track sookshikkaan aantharika hardware illa. atharam pala niyanthrana samvidaanangalum baahya samayathekkurichu ariyaathe pravartthikkunnu. atharam vivarangal aavasyamullavar saadhaaranayaayi reboot cheyyumbol time serveril ninno ekstenal klokkil ninno polulla oru ekstenal sozhsil ninnu nilavile samayam nedunnathiloodeyo nilavile samayam swamedhayaa nalkaan upayokthaavine prerippikkunnathiloode avarude bays time aarambikkunnu.
nadappaakkal.
sipiyuvine idaykkide thadassappeduthunna prograamabil interwell timeraayi sisttam clock saadhaaranayaayi nadappilaakkunnu, athu pinneedu oru timer interpettu sarvees rutin nadappilakkaan thudangunnu. eee pathiv saadhaaranayaayi sisttam klokkilekku (oru lalithamaaya kaundar) oru tick cherkkukayum mattu aanukaalika house keeping jolikal (preemption muthalaayava) kaikaaryam cheyyukayum cheiyunnu.) joliyilekku madangunnathinumumbu sii. pii. yuu thadassathinu munbu nadappilaakkukayaayirunnu.
sisttam samayam veendedukkunnu.
vividha operating sisttangal, prograaming bhashakal, aaplikkeshanukal ennivayil sisttam samayam veendedukkunnathinulla reethikal inipparayunna pattikakal vyakthamaakkunnu. (*) ennu adayaalappeduthiya moolyangal systethe aasrayichirikkunnu, avaa nadappaakkalukalil vyathyasthamaayirikkam. ellah theeyathikalum gregorian allengil proleptik gregorian kalandar theeyathikalaayi nalkiyittundu.
oru nadappaakkalinte samaya alavinte pariharam atharam alavukalude athe krithyathaye soochippikkunnilla ennathu shradhikkuka. udaaharanathinu, oru sisttam micro secondil alakkunna moolyamaayi nilavile samayam nalkiyekkaam, pakshe yadhaarthathil 100 hearts (10 millie) freekwansiyil vyakthigatha clock tikkukal thirichariyaan kazhiyum.

