Init mubereki wezvinhu zvose. Basa rayo guru nderokusika maitiro kubva mune script yakachengetwa mufaira / etc / inittab (ona inittab (5)). Iyi faira inowanzo ine zvinyorwa zvinokonzera init kukonzera getty s kumurongo wega wega wevashandisi vanogona kupinda. Uyewo inodzora zvigadziro zvinotarisirwa zvinodiwa nemumwe mutemo.
Runlevels
A runlevel isupurogiramu ye-software ye system inobvumira chete boka rakasarudzwa remitemo kuti rivepo. Izvo zvakagadzirwa ne init yeimwe yezvipikisa zvinotsanangurwa mu / etc / inittab faira. Init inogona kuva mune imwe ye8 runlevels: 0-6 uye S kana s . Iyo runlevel inoshandiswa nekuva nemunhu anoshandisa runhare tereinit , iyo inotumira zviratidzo zvakakodzera ku init , ichiudza iyo runlevel kuchinja.
Runlevels 0 , 1 , uye 6 dzakachengetedzwa. Runlevel 0 inoshandiswa kumisa purogiramu, runlevel 6 inoshandiswa kugadzirisa purogiramu yacho, uye runlevel 1 inoshandiswa kuita kuti system irambe ichienda kune imwe user mode. Runlevel S haisi kureva kushandiswa kushandiswa zvakananga, asi zvimwe zvezvinyorwa zvinourawa paunopinda runlevel 1. Kuti uwane mamwe mashoko pamusoro peizvi, ona manpages ekuvhara (8) uye inittab (5).
Runlevels 7-9 inoshandawo, kunyange isinganyatsorongororwa. Izvi ndechokuti "tsika" dzeku Unix dzakasiyana siyana hadzisashandisi. Kana iwe uchida kuziva, runlevels S uye s zviri chaizvo zvakafanana. Pakati pavo ivo vanofananidzirwa kune rimwechete runlevel.
Booting
Mushure mokunge init inoshandiswa sechigarire chekupedzisira chekernel boot sequence, inotarisa faira / etc / inittab kuona kana kune mukana wechimiro initdefault (ona inittab (5)). Iyo initdefault inopinza inotanga runle runlevel yemutambo. Kana pasina kuiswa kwakadaro (kana kwete / etc / inittab zvachose), a runlevel inofanira kuiswa pa system console.
Runlevel S kana s inounza system kuti isarudze user mode uye haifaniri i / etc / inittab faira. Mune rimwe chete user mode, mudzi wezodzi yakazarurwa pa / dev / console .
Paunopinda single user mode, init inodaro iyo console ioctl (2) inoti kubva /etc/ioctl.save . Kana iyi faira isipo, init inotanga mutsara pa 9600 baud uye neCLOCAL zvirongwa. Apo init mashizha asina kushandisa user mode, inochengetedza zvirongwa zve ioctl mune iyi faira saka inogona kuzvishandisa zvakare kune imwe inotevera musangano wevashumiri.
Paunopinda maitiro akawanda-user for first time, init inogadzira zvinyorwa zvebhoot uye bootwait kuti zvibvumirano zvefaira zvigadziriswe vasati vashandise vangapinda mazviri. Zvadaro zvinyorwa zvose zvinoenderana ne runlevel zvinoshandiswa.
Kana uchitanga nzira itsva, init inotanga kuona kana faira / etc / initscript iripo. Kana ikashanda, inoshandisa script iyi kuti itange iyo nzira.
Nguva imwe neimwe kana mwana apedza, init zvinyorwa zvokwadi uye chikonzero chakafa mu / var / run / utmp uye / var / log / wtmp , kunze kwekuti mafaira aya aripo.
Kuchinja Runlevels
Mushure mokunge yaita zvose zvinenge zvataurwa, init inomira kune imwe yerudzi rwayo nzira yekufa, chiratidzo che powerfail, kana kusvika ichiratidzwa neTelinit kuti ichinje kugadzirisa kwemaitiro. Apo chimwe chezvinhu zvitatu zviri pamusoro apa chinowanika, chinoongorora zvakare / etc / inittab file. Zvinyorwa zvitsva zvinogona kuwedzerwa kune iyi faira chero nguva. Zvisinei, init ichiri kumirira chimwe chezvinhu zvinopfuura zvitatu zviri pamusoro apa kuti zviitike. Kuti ipe rubatsiro rwechimbichimbi , tereinit Q kana mutungamiri q inogona kumutsa init kuti iongorore zvakare / etc / inittab faira.
Kana init isati iri mune imwe user mode uye inogamuchira signalfail powerfail (SIGPWR), inoverenga faira / etc / powerstatus . Iyo inotanga mutemo unobva pane zviri mukati pefaira iyi:
F (AIL)
Simba iri kukundikana, UPS iri kupa simba. Dzorera simba rekushandisa uye powerfail .
O (K)
Simba rakadzorerwa, ita zvinyorwa zvine simba.
L (OW)
Simba iri kukundikana uye UPS ine bateri yakadzika. Dzorera zvinyorwa zvine simba.
Kana / etc / powerstatus isipo kana kuti ine chimwe chinhu ipapo tsamba F , O kana L , init ichazvibata sekuti yakaverenga tsamba F.
Kushandiswa kweSIGPWR uye / etc / powerstatus kunoodzwa mwoyo. Mumwe munhu anoda kushamwaridzana ne init anofanira kushandisa shanduro ye / dev / initctl - ona chinyorwa ches sysvinit pakuronga mamwe magwaro pamusoro peizvi.
Apo init inokumbirwa kushandura runlevel, inotumira chiratidzo chenyevero SIGTERM kune zvese zvinenge zvisingatsananguki mune itsva runlevel. Icho chinomirira mashomanana mashanu musati wanyatsogadzirisa matanho aya kuburikidza nechiratidzo cheSIGKILL . Cherechedza kuti init inofunga kuti izvi zvose zvinotsika (uye vana vavo) vanoramba vari muboka rimwechete reboka iro init pakutanga rakagadzirirwa ivo. Kana imwe nzira inoshandura iyo nzira yekubatana kweboka hakuzogamuchiri zviratidzo izvi. Izvi zvinoda kubviswa zvakasiyana.
Telinit
/ sbin / telinit inobatanidza ne / sbin / init . Zvinotora nharo imwe-nhengo uye zviratidzo zve init kuitira chiito chakakodzera. Nharo dzinotevera dzinoshandiswa semirairo kune telinit :
0 , 1 , 2 , 3 , 4 , 5 kana 6
taurira init kuti tishandure kune yakananga kumhanya.
a , b , c
taurira init kuti iongorore chete iyo / etc / inittab mafaira okupinda ane runlevel a , b kana c .
Q kana q
taura init kuti uongorore zvakare / etc / inittab faira.
S kana s
taurira init kuti tishandure kune imwe yerudzi rwemhando.
U kana iwe
taurira init kuti izvidzore zvakare (kuchengetedza nyika). Kwete kuongororazve / / etc / inittab faira inoitika. Runza yepamusoro inofanira kuva imwe yeSs12345 , zvisinei kuti chikumbiro chingave chinyararire.
telinit inogonawo kutaura init kuti inguva yakareba sei inofanira kumirira pakati pekutumira nzira SIGTERM uye SIGKILL zviratidzo. Izvo zvisipo ndeye mashure mashanu, asi izvi zvinogona kuchinjwa ne -t sec sechisarudzo.
telinit inogona kungoshandiswa chete nevashandisi vane ropafadzo dzakakodzera.
Iko init binary checks kana iri init kana telinit nekutarisa pane yatoita id ; iyo chai init 's process process nguva dzose 1 . Kubva pane izvi zvinotevera kuti panzvimbo yekudana tereinit imwe inogonawo kushandisa init pane nzira shoma.