Umyalelo wokuvavanya ungasetyenziselwa kumgca we-Linux umyalelo wokuqhathanisa iqela elinye kunye nelinye kodwa lisetyenziswe ngokubanzi kwi- BASH ze-shell zeempendulo njengengxenye yezitatimende ezingqinelanayo ezilawula umongo kunye nenkqubo yokuhamba.
Umzekelo Oyisiseko
Unokuzama le miyalelo ngokuvula iwindi yokugcina .
vavanyo 1 -eq 2 && echo "ewe" || phendula "akukho"
Umyalelo ongentla ungaphulwa ngolu hlobo lulandelayo:
- vavanyo - oku kuthetha ukuba uzimisele ukuthelekisa
- 1 - into yokuqala oya kuthelekisa
- -eq (unjani ukuthelekisa, kulo mzekelo, uvavanya ukuba inani elinye lilingana nelinye)
- 2 - isalathisi othelekisa into yokuqala
- && - sebenzisa le nkcazo elandelayo ukuba isiphumo siyinyaniso
- phendula "ewe" - umyalelo wokusebenza xa ukuthelekiswa kubuyisela
- || - sebenzisa le nkcazo elandelayo ukuba isiphumo simanga
- phendula "akukho" - umyalelo wokusebenza xa ukuthelekisa kubuya buxoki
Ngokwenene, umyalelo uqhathanisa u-1 ukuya ku-2 kwaye bafana ne-echo "yebo" ingxelo eyenziwa ebonisa "yee" kwaye ukuba ayifani nento echaziweyo "ayikho" isingqinisiso esenziwa ebonisa "akukho".
Ukuthelekisa amanani
Ukuba uthelekisa izinto ezigqithiseleyo njengeenombolo ongazisebenzisa ezi zinto zilandelayo:
- -eq - ixabisa ixabiso elilinganayo eli-2
- -ge - lixabiso elikhulu 1 okanye lilingana nexabiso 2
- -gt - lixabiso 1 likhulu kunexabiso 2
- -le - lixabiso 1 ngaphantsi okanye lilingana nexabiso 2
- -in - ixabiso 1 ngaphantsi kwexabiso 2
- -ne-ayixabisi 1 ayilingani ixabiso elilinganayo 2
U mzekelo:
vavanyo 1 -eq 2 && echo "ewe" || phendula "akukho"
(ibonisa "akukho" kwiskrini kuba 1 ayilingani 2)
vavanyo 1 -ka-2 && echo "ewe" || phendula "akukho"
(ibonisa "akukho" kwisikrini ngoba 1 ayikho mkhulu okanye ilingana no-2)
vavanyo 1 -gt 2 && echo "ewe" || phendula "akukho"
(ibonisa "akukho" kwiskrini kuba 1 ayikho ngaphezu kwe-2)
vavanyo 1 -le 2 && echo "ewe" || phendula "akukho"
(ibonisa "yebo" kwisikrini kuba 1 ingaphantsi okanye ilingana no-2)
vavanyo 1 -lt 2 && echo "ewe" || phendula "akukho"
(ibonisa "yebo" kwisikrini kuba 1 ingaphantsi okanye ilingana no-2)
vavanyo 1 -ne-2 && echo "ewe" || phendula "akukho"
(ibonisa "yebo" kwisikrini kuba i-1 ayilingani 2)
Ukuthelekisa Umbhalo
Ukuba uthelekisa izinto ezigqithiseleyo njengemida, ungasebenzisa aba bathengisi beendlela ezilandelayo:
- = - uyenza intambo yomtya wokulinganisa 2
- ! = - umtya 1 ohlukileyo kumtya 2
- -n - umgca ubude obukhulu kunama-0
- -i - ngumtya wocingo ubude 0
U mzekelo:
vavanyo "umtya1" = "string2" && echo "ewe" || phendula "akukho"
(ibonisa "akukho" kwiskrini ngoba "intambo1" ayilingani "string2")
vavanya "umtya1"! = "string2" && echo "ewe" || phendula "akukho"
(ebonisa "ewe" kwesikrini ngoba "umtya 1" awufanani "nomtya2")
vavanyo -i "string1" && echo "ewe" || phendula "akukho"
(ebonisa "ewe" kwesikrini ngoba "umtya 1" unomtya ophezulu ngaphezu kwezinga)
vavanyo -t "string" "&& echo" ewe "|| phendula "akukho"
(ibonisa "akukho" kwiskrini ngoba "umtya 1" unomtya ophezulu ngaphezu kwezinga)
Ukuthelekisa iiFayile
Ukuba uthelekisa iifayile ungasebenzisa aba bathengisi beendlela ezilandelayo:
- -ef - Ngaba iifayile zinesixhobo esifanayo kunye neenode zeenode (ngaba iifayile enye)
- -nt - Ngaba iifayile yokuqala intsha kunefayile yesibini
- -ot - Ngaba ifayile yokuqala ikhulile kunefayile yesibini
- -b - Ifayile ikhona kwaye ivimba okhethekileyo
- -c - Ifayile ikhona kwaye ingumntu okhethekileyo
- -d - Ifayile ikhona kwaye iyincwadi
- -e - Ifayile ikhona
- -f - Ifayile ikhona kwaye iifayile eziqhelekileyo
- -g - Ifayile ikhona kwaye inenombolo yeqela elichaziweyo
- -G - Ifayile ikhona kunye nomnikazi ngeqela lomsebenzisi
- -h - Ifayile ikhona kwaye ikhonkco lokufuzisela
- -k - Ifayile ikhona kwaye inobungozi bayo bume
- -L - efanayo -h
- -O - Ifayile ikhona unomnini
- -p - Ifayile ikhona kwaye ibhobho ebizwa ngegama
- -r - Ifayile ikhona kwaye iyafundwa
- -s - Ifayile ikhona kwaye inobungakanani obukhulu kunezinga
- -S - Ifayile ikhona kwaye isiseko
- -t - I-descriptor yefayile ivuliwe kwi-terminal
- -u - Ifayile ikhona kunye ne-set-user-id id isethi
- -w - Ifayile ikhona kwaye ibhaliwe
- -x - Ifayile ikhona kwaye iyenzeka
U mzekelo:
vavanyo / indlela / ukuya kwifayile1 -n / umzila / ukuya / fayile2 && echo "ewe"
(Ukuba ifayile1 intsha kunefayile2 ke igama elithi "ewe" liya kuboniswa)
vavanyo -e / umzila / ukuya / fayile1 && echo "ewe"
(ukuba ifayile1 ikhona igama elithi "ewe" liya kuboniswa)
vavanyo -O / umzila / ukuya / fayile1 && echo "ewe"
(ukuba unayo ifayile1 ke igama elithi "ewe" liboniswa ")
I sigama
- Ukukhusela okhethekileyo - Ifayile iyisisithi yebhloko esithetha ukuba idatha ifundwa kwiibhloko zeete. Ezi ziqhelekileyo zifayili zesefowuni ezifana nokuqhuba kanzima.
- Umntu okhethekileyo - Ifayile isetyenziswa ngokukhawuleza xa ubhalela kuyo kwaye ngokuqhelekileyo ifowuni enjenge-port serial
Ukuthelekisa iziganeko ezininzi
Ngaloo nto yonke into iqhathanise into enye nenye kodwa kuthekani ukuba ufuna ukuthelekisa iimeko ezimbini.
Umzekelo, ukuba isilwanyana sinemilenze emine kwaye iya "apho" mhlawumbi yinkomo. Ukujonga nje imilenze emine akuqinisekisi ukuba unenkomo kodwa ukhangele isandi esenzayo ngokuqinisekileyo.
Ukuvavanya zombini iimeko ngokukhawuleza basebenzise la mazwi alandelayo:
vavanyo 4 -eq 4 -a "moo" = "khona" && echo "yinkomo" || bhala "akusiyo inkomo"
Inxalenye ephambili apha i-emele kwaye.
Kukho indlela engcono kwaye isetyenziswa ngokuqhelekileyo yokuqhuba uvavanyo olufanayo kwaye lulo lulandelayo:
vavanyo 4 -eq 4 && test "apho" = "khona" && echo "yinkomo" || bhala "akusiyo inkomo"
Olunye uvavanyo onokufuna ukuyenza luthelekisa izitatimende ezimbini kwaye ukuba ngaba yinyani ivelisa umtya. Umzekelo, ukuba ufuna ukujonga ukuba ifayile ebizwa ngokuthi "file1.txt" ikhona okanye ifayile ebizwa ngokuthi "file1.doc" ikhona ungasebenzisa lo myalelo olandelayo
vavanyo -i file1.txt -o -e file1.doc && echo "ifayile1 ikhona" || bhala "ifayile1 ayikho"
Inxalenye ephambili apha yi -o emele okanye.
Kukho indlela engcono kwaye isetyenziswa ngokuqhelekileyo yokuqhuba uvavanyo olufanayo kwaye lulo lulandelayo:
vavanyo -e file1.txt || vavanyo -i file1.doc && echo "ifayile1 ikhona" || bhala "ifayile1 ayikho"
Ukuqeda uvavanyo lwegama elingundoqo
Akunakudingi ukuba usebenzise ukuhlolwa kwegama ukwenza uthelekiso. Konke okufuneka ukwenze ukufaka inkcazo kwiibhanki ezikrelekre ngokulandelayo:
[-i file1.txt] && echo "ifayile1 ikhona" || bhala "ifayile1 ayikho"
I [kwaye] isho ngokufanayo ukufana novavanyo.
Ngoku uyazi oku unokuphucula ngokuthelekisa iimeko ezininzi ngale ndlela:
[4 -eq 4] && ["apho" = "khona"] && echo "yinkomo" || bhala "akusiyo inkomo"
[-i file1.txt] || [-i file1.doc] && echo "ifayile1 ikhona" || bhala "ifayile1 ayikho"
Isishwankathelo
Umyalelo wokuvavanya uncedo ngakumbi kwizikripthi ngenxa yokuba unokuvavanya ixabiso lentlobo enye ngokubhekiselele kwelinye kunye nolawulo lwenkqubo yokuhamba. Ngomgca womyalelo womgangatho, ungayisebenzisa ukuvavanya ukuba ikhona ifayile okanye