Njengomphathi wesistimu ye-Linux, izikhathi eziningi, uzongena ezimeni lapho udinga ukukhohlisa futhi ufomethe kabusha okukhiphayo okuvela emiyalweni eyahlukene, ukuze umane ubonise ingxenye yokuphumayo ngokuhlunga imigqa embalwa. Le nqubo ingabizwa ngokuthi ukuhlunga umbhalo, kusetshenziswa iqoqo lezinhlelo ze-Linux ezaziwa njengezihlungi.
Kunezinsiza eziningana ze-Linux zokuhlunga umbhalo futhi ezinye zezihlungi ezaziwa kakhulu zifaka ikhanda, umsila, i-grep, i-tr, i-fmt, uhlobo, i-uniq, i-pr namathuluzi athuthuke kakhulu futhi anamandla njenge-Awk ne-Sed.
Funda kabanzi →Kusukela ekuqaleni kochungechunge lwe-Awk kuze kufike kuNgxenye 12, besibhala imiyalo emincane ye-Awk nezinhlelo emugqeni womyalo nakumbhalo wegobolondo ngokulandelana.
Nokho, i-Awk, njengoba nje uShell, iwulimi oluhunyushiwe, ngakho-ke, ngakho konke esidlule kukho kusukela ekuqaleni kwalolu chungechunge, ungakwazi manje ukubhala imibhalo esebenzisekayo ye-Awk.
Ngokufanayo nendlela esibhala ngayo iskripthi segobolondo, imibhalo ye-Awk iqala ngomugqa:
#! /path/to/awk/utility -fIsibonelo kusistimu yami, insiza ye-Awk itholakala ku-/usr/bin/awk, ngakho-ke, ngizo
Funda kabanzi →Uma ubuyekeza zonke izibonelo ze-Awk esesizisebenzisile kuze kube manje, zisuka nje ekuqaleni komsebenzi wokuhlunga umbhalo ngokusekelwe kwezinye izimo, kulapho indlela yezitatimende zokulawula ukugeleza iqala khona.
Kunezitatimende ezahlukahlukene zokulawula ukugeleza ezinhlelweni ze-Awk futhi lezi zihlanganisa:
Uma sibhala imibhalo yegobolondo, ngokuvamile sihlanganisa ezinye izinhlelo ezincane noma imiyalo efana nokusebenza kwe-Awk emibhalweni yethu. Endabeni ye-Awk, kufanele sithole izindlela zokudlulisa amanani athile ukusuka kugobolondo ukuya emisebenzini ye-Awk.
Lokhu kungenziwa ngokusebenzisa okuguquguqukayo kwegobolondo ngaphakathi kwemiyalelo ye-Awk, futhi kule ngxenye yochungechunge, sizofunda ukuthi singayivumela kanjani i-Awk ukuthi isebenzise okuguquguqukayo kwegobolondo okungase kuqukathe amanani esifuna ukuwadlulisela kumiyalo ye-Awk.
Kunezindlela ezimbili ongavumela ngaz
Funda kabanzi →Njengoba sembula isigaba sezici ze-Awk, kule ngxenye yochungechunge, sizohamba emcabangweni wokuguquguquka okwakhelwe ngaphakathi ku-Awk. Kunezinhlobo ezimbili zokuguquguquka ongazisebenzisa ku-Awk, lezi yizi; okuguquguqukayo okuchazwe ngumsebenzisi, esikuhlanganise kuNgxenye 8 neziguquguqukayo ezakhelwe ngaphakathi.
Okuguquguqukayo okwakhelwe ngaphakathi kunamanani asechazwe kakade ku-Awk, kodwa fu
Funda kabanzi →Uchungechunge lomyalo we-Awk luyajabulisa ngiyakholwa, ezingxenyeni eziyisikhombisa ezedlule, sidlule kwezinye izinto eziyisisekelo ze-Awk okudingeka wazi kahle ukuze ukwazi ukwenza umbhalo oyisisekelo noma ukuhlunga izintambo ku-Linux.
Ukuqala ngale ngxenye, sizocwila ezindaweni ezingaphambili ze-Awk ukuze sibambe imibhalo eyinkimbinkimbi noma imisebenzi yokuhlunga iyunithi yezinhlamvu. Ngakho-ke, sizofaka izici ze-Awk ezifana neziguquguqukayo, izinkulumo zezinombolo kanye nabaqhubi bezabelo.
Funda kabanzi →Ezingxenyeni zangaphambilini zochungechunge lwethuluzi le-Awk, sibheke okokufaka kokufunda ikakhulukazi kufayela(ama), kodwa kuthiwani uma ufuna ukufunda okokufaka okuvela ku-STDIN.
Kulolu chungechunge lweNgxenye yesi-7 ye-Awk, sizobheka izibonelo ezimbalwa lapho ungakwazi ukuhlunga okukhiphayo kweminye imiyalo esikhundleni sokufunda okokufaka efayeleni.
Sizoqala ngomyalo we-ls, esibonelweni sokuqala esingezansi, sisebenzisa okukhiphayo komyalo we-dir -l njengokufakwayo kwe-Awk ukuze iphrinte igama lomsebenzisi lomnikazi, igama leqembu kanye namafayela anawo okwaman
Funda kabanzi →Kule ngxenye yesithupha yochungechunge lwe-Awk, sizobheka ukusebenzisa umyalo othi olandelayo, otshela i-Awk ukuthi yeqe wonke amaphethini nezisho ezisele ozinikezile, kodwa kunalokho ifunde umugqa wokufaka olandelayo.
Umyalo
Ukuze siqonde ukuthi isebenza kanjani, ake sicabangele ifayela elibizwa ngokuthi food_list.txt elibukeka kanje:
No Item_Name Price Quantity 1 Mangoes Funda kabanzi →Sonke lesi sikhathi, besilokhu sibheka izinkulumo ezilula lapho sibheka ukuthi umbandela othile ufinyelelwe yini noma cha. Kuthiwani uma ufuna ukusebenzisa isisho esingaphezu kwesisodwa ukuze uhlole isimo esithile?
Kulesi sihloko, sizobheka ukuthi ungahlanganisa kanjani izinkulumo eziningi ezibizwa ngokuthi izinkulumo ezihlanganisiwe ukuze uhlole isimo lapho uhlunga umbhalo noma iyunithi yezinhlamvu.
Ku-Awk, izinkulumo ezihlanganisiwe zakhiwa kusetshenziswa
Uma usebenzisana namanani ezinombolo noma eyunithi yezinhlamvu emgqeni wombhalo, ukuhlunga umbhalo noma iyunithi yezinhlamvu usebenzisa ama-opharetha wokuqhathanisa kuyasiza kubasebenzisi bomyalo be-Awk.
Kule ngxenye yochungechunge lwe-Awk, sizobheka ukuthi ungahlunga kanjani umbhalo noma iyunithi yezinhlamvu usebenzisa ama-opharetha wokuqhathanisa. Uma ungumhleli kufanele ukuthi usujwayelene nabasebenza ngokuqhathanisa kodwa abangabazi, ake ngichaze esigabeni esingezansi.
Ama-opharetha wokuqhathanisa ku-Awk asetshenziselwa ukuqhathanisa inani lezinombolo noma amayunithi ezinhla
Funda kabanzi →