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[Powered by Google Translate] GDB, GNU Mradi Debugger, ni nguvu debugging chombo kwa ajili ya C,

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pamoja na lugha nyingine nyingi.

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Ni inaruhusu wewe poke kuzunguka ndani ya mipango yako C wakati wao ni utekelezaji,

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na pia inakupa fursa ya kuona nini hasa kinatokea

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wakati mpango wako shambulio.

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Ni pretty nifty, haki?

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GDB ni programu za bure, na anaendesha katika UNIX wengi maarufu na

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Makao Windows mifumo ya uendeshaji, hivyo ni chombo sana kuenea.

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>> Unapaswa kujifunza kupenda.

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GDB faida na muda mwingi rahisi kufuatilia chini mende

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zaidi kuliko wale ambao chafuko njia ya kutumia guesses

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na usio kiasi wa taarifa printout.

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GDB ni chombo amri-line, ambayo ina maana unaweza kuingiliana na katika terminal

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kutoa amri kupitia keyboard badala ya vifungo kubonyeza na mouse yako.

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>> Kuanzisha GDB, wewe literally aina tu gdb katika haraka na hit kuingia.

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Utaona mistari baadhi kuchapishwa kwa screen

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kuonyesha toleo la GDB kwamba wewe ni mbio,

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hati miliki yake ya habari, na mwishoni utaona haraka GDB: (gdb).

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Hii inakuwezesha kujua kwamba GDB ni tayari kwa amri.

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Katika hatua hii, jambo muhimu zaidi kujua jinsi ya kufanya ni kuacha.

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Bahati nzuri, hii ni pretty rahisi.

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amri kujiondoa anafanya tu.

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Kama njia ya mkato, unaweza kutumia tu q pia.

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Kama furaha kama booting up GDB na kisha mara moja kuacha ni,

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hebu sasa kuzungumza kuhusu kutumia GDB kusaidia Debug mpango.

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>> Kuanza, mimi nimepata mpango hapa katika factorial.c

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kwamba anapata int na majaribio ya compute factorial wake.

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Katika kesi hawajaona factorials kabla au sikumbuki yao,

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factorial ya idadi n ni sawa na bidhaa ya n - (n - 1), (n - 2), na kadhalika -

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mpaka hit 1.

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Kwa hiyo, factorial ya 3 ni 3 * 2 * 1, au 6,

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na factorial ya 4 ni 4 * 3 * 2 * 1, au 24.

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factorial ya sifuri ni kesi ya isiyo ya kawaida, ni 1,

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na factorials ya integers hasi si defined.

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Anyway, kitu kuhusu mpango wangu factorial ni funky.

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Wakati mimi kukimbia, ni Prints nje idadi weird kuwa na kitu cha kufanya na factorials.

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>> Hivyo, tunaweza kutumia GDB kusaidia kufikiri nini kinaendelea.

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GDB kazi kwenye files executable,

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ambayo ni files binary zinazozalishwa na mchakato mkusanyiko.

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Hiyo ni, hatuwezi kuendesha GDB juu ya c wetu. Au h chanzo code files kama factorial.c..

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Tunataka kukimbia juu tu factorial badala yake.

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Kama mpango required hoja amri yoyote-line,

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hii ni mahali ambapo tunatarajia bayana kwao.

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Katika kesi hiyo, factorial hauhitaji hoja amri yoyote-line,

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hivyo sisi aina tu kukimbia au r kwa muda mfupi.

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>> Hii itaanza factorial mpango mbio.

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Wakati mpango ataacha mbio, mimi nitachukua GDB yangu kuchochea nyuma.

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Okay, hebu jaribu kitu kimoja tena, factorial ya 4.

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Haki zote, tunaona kwamba sisi ni kupata aina moja ya Junk hapa katika GDB.

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Sasa kwamba mpango ina kumaliza,

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hatuwezi kwenda katika na kupata yoyote ya hali yake,

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hivyo tutaweza haja ya kuanza ni kukimbia tena kabla tunaweza kuona nini kinatokea.

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Hata hivyo, tunahitaji njia ya kuacha ni wakati ni katikati ya kukimbia wake.

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>> Ili kufanya hivyo, sisi kutumia kile kinachoitwa breakpoint.

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Breakpoints kuwaambia GDB pause programu katika kazi fulani au chanzo line code

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ili tuweze kuangalia hali ya mpango,

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maadili ya vigezo, hali ya kumbukumbu na vile, katika hatua hiyo.

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Tangu mimi si kweli kujua ambapo mambo yanaenda vibaya,

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>> Mimi nataka tu kuanza debugging haki katika mwanzo sana,

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haki wakati kuu huanza.

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Tutaweza kuweka breakpoint katika mwanzo wa kuu kwa kutumia amri ya mapumziko.

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Tunaweza pia kutumia b abbreviate mapumziko.

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Sasa hebu kuanza mpango wa kukimbia tena.

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Hapa sisi ni mwanzo wa kuu, kama GDB inatuambia.

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mstari wa kanuni hiyo kuhusu kutekeleza lakini bado ana

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ni mstari printf.

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Tunaweza kuwaambia GDB kutekeleza huu mstari wa kanuni na kwenda mstari unaofuata

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na amri ya pili au n.

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>> Haki zote, sasa GDB inatuambia kwamba sisi ni juu ya mstari GetInt.

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Mimi najua kwamba inaonekana kama mstari printf havijawa

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tangu hatuoni "Ingieni chanya integer" magazeti nje kwenye screen,

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lakini hakuwa kweli kukimbia.

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Nini sisi ni kuona ni mfumo wa uendeshaji kukandamiza kuandika chochote kwa screen

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mpaka kabisa ina, ambayo kwa nini debugging na nakala zake

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wakati mwingine unaweza kuonekana uhakika.

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Anyway, hebu tena kwenda line ya pili ya kificho na kuingia katika int.

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Tena, hebu aina 4.

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Hivyo hii inaonekana weird. Sisi ni juu ya mstari 12 kulingana na GDB,

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lakini mstari unaofuata hiyo kuhusu kutekeleza ni tu Brace curly.

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>> Hiyo ina maana sisi ni saa ya mwisho wa kitanzi, yetu kufanya wakati kitanzi kwa kweli,

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na GDB anatuambia kwamba hali kusitishwa, yaani hakuna chini ya sifuri,

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nitafanya ijayo.

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Kama hii milele anapata utata kidogo,

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tunaweza kuvuta chanzo code katika GDB na orodha au amri l.

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Hii Prints nje chanzo code

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hiyo ni unaozingatia kuzunguka mstari kwamba sisi ni sasa juu.

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Kama sisi aina orodha au l tena, tutaweza kuona seti ya pili ya mistari magazeti nje.

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Tunaweza kufanya hili mpaka sisi hit mwisho wa faili.

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>> Ili kupata nyuma ambapo tulikuwa, tunaweza ugavi orodha na idadi ya mstari,

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katika kesi hii, line 12.

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Anyway, hebu kuendelea.

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Sasa sisi ni juu ya kitanzi 4.

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Hebu kuhakikisha kwamba num yetu ina variable 4.

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Sisi kufanya pamoja na magazeti, au p, amri.

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Hivyo, GDB inatuambia kwamba num ni kweli hifadhi 4, kama tulivyotarajia.

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$ 1 GDB kwamba Prints nje ni maalum GDB variable

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kwamba sasa ni kuweka na kuhifadhi 4 idadi kama vizuri.

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Unaweza kupuuza hii kwa sasa, lakini vigezo GDB haya kuja katika Handy super

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katika kesi zaidi ya juu wakati unataka kukumbuka nini umefanya kosa huko nyuma.

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Anyway, kuhama kwa pili, tunaona kwamba sisi kuanza kusonga kupitia kwa kitanzi.

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Hebu kuendelea kupitia hapa na kidogo n kidogo.

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Badala ya kuandika n kila wakati, unaweza pia tu hit kuingia.

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Wakati wewe hit kuingia bila kuandika chochote, GDB tu akarudisha amri uliopita.

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Hivyo sasa tumekuwa hit wito printf.

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Inaonekana kama tumekuwa kweli wamekwenda kupitia wetu kwa kitanzi mara 4,

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ambayo ni nini tunataka kufanya ili kuzidisha kwa 1, 2, 3, na 4.

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>> Kila kitu inaonekana kama ni kazi,

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ila wakati sisi hit ijayo tena sisi kupata idadi hii kubwa badala ya 24.

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Kama sisi magazeti nje thamani ya p factorial kutumia,

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tunaona kwamba factorial gani kuwa hii idadi kubwa ndani yake.

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Kitu ambacho dhahiri kwenda vibaya.

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Katika hatua hii, ingawa, sisi ni karibu ya mwisho wa mpango,

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na ni kuchelewa mno kurekebisha kitu chochote.

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>> Hata hivyo, tunaweza kuanzisha upya mpango kwa kuandika r tena na kisha y kuthibitisha.

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Sasa tuko nyuma katika breakpoint yetu katika mwanzo wa kuu.

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Tunajua kwamba kila kitu inaonekana kuwa nzuri na kusoma katika n.

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hivyo tunaweza kuruka mbele na n.

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Vinginevyo, tunaweza kuweka breakpoint mpya baada ya kufanya wakati kitanzi

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na kuruka huko. Hebu kufanya hivyo.

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Inaonekana kama mstari 14 inakuja tu baada ya kitanzi.

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Hebu kuweka breakpoint huko.

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Ni vizuri mazoezi ya kubainisha jina faili katika amri hii breakpoint

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tangu GDB wanaweza kupata kuchanganyikiwa kama wewe ni kufanya kazi na files nyingi.

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Kusonga mbele ya breakpoint hii, tutaweza kutumia kuendelea au c amri.

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>> Okay, hapa sisi ni wakati kwa kitanzi.

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Hebu kwenda 1 zaidi katika mstari kwa kitanzi,

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na kisha tutaweza kuanza vigezo uchapishaji kuona nini kinaendelea.

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Hebu kuhakikisha kwamba i ni kweli 1, kama ilivyotarajiwa.

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Yup, kwamba ni yote mema.

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Je kuhusu factorial ingawa?

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Ho, kwamba hakuna jema.

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Sisi tumepewa kubwa hasi idadi hapa.

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How'd kwamba kutokea?

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Naam, kama sisi kuangalia nyuma katika kificho,

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tunaona kwamba sisi kamwe initialized hivyo, hivyo tumekuwa tu got takataka katika huko.

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Ambayo dhahiri kutupa mbali hesabu zetu.

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>> Bahati nzuri, hatuna kuondoka GDB kurekebisha hii.

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Tunaweza initialize ni haki hapa na kurekebisha katika code baadaye kwa kutumia amri ya kuchapisha.

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Tutaweza initialize kwa 1 tangu factorials ya sifuri na 1 ni wawili 1,

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na kama sisi initialize kwa sifuri, basi tunatarajia daima kuishia na sifuri kama matokeo yetu.

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Unaweza kuweka yoyote kutofautiana kwa njia hii, ambayo ni super Handy.

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Sasa, hebu kuendelea na mpango wetu.

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Hebu kuhakikisha kila kitu ambapo ni walidhani kuwa.

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Hes lazima 4, i lazima 1, na factorial lazima 1 pia.

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Tunaweza mkato mchakato huu na magazeti yote ya vigezo yetu ya ndani

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na super-kusaidia amri info wenyeji,

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ambayo Prints nje wote wa-wigo katika vigezo yetu ya ndani.

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Anyway, inaonekana kama kila kitu ni vizuri kwenda.

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>> Hebu kufanya mwingine go-kuzunguka ya kitanzi tu kuhakikisha.

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Sawa, kila kitu inaonekana kubwa.

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Sasa tunaweza kuendelea kutumia amri ya kwenda hadi mwisho.

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Tamu! 4 factorial kuchapishwa 24 kama ilivyotarajiwa.

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Sasa tunaweza kwenda kurekebisha hii katika code yetu.

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Badala ya kujiondoa kutoka GDB, tutaweza kutumia mwingine tab terminal kufanya hili.

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Tukirudi kwenye GDB tab yetu, sisi sasa haja ya recompile executable yetu.

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Moja ya mambo bora kuhusu GDB ni kwamba huna haja ya kuondoka GDB kuendesha kufanya.

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Hivyo kwamba hatuwezi kuendelea kupiga breakpoints zamani,

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hebu kuzilemaza na, wewe guessed it, afya amri.

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Hii italemaza wote wa breakpoints yetu.

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Sasa, tunaweza kuanzisha upya mpango na r na kuhakikisha kila kitu ni sawa.

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Inaonekana kama kila kitu ni vizuri kwenda.

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Factorial ya prints 4 nje 24, tu kama sisi mawazo.

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GDB ni moja ya zana na manufaa zaidi nimepata katika Vifaa yako.

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>> Kuna tani zaidi ya mambo unaweza kufanya na GDB,

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mbali zaidi kuliko unaweza kufanya na nakala zake rahisi.

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Next wakati mpango wako si kufanya nini ungependa,

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kujaribu kukimbia GDB kufikiri nini kinaendelea ndani.

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Na kidogo ya mazoezi, wewe utakuwa na uwezo wa kuchimba chini kulia juu ya mdudu wako katika wakati hakuna.

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Jina langu ni Nate Hardison. Hii ni CS50.