Malinga ndi Wikipedia, metacharacter ndi khalidwe lililonse lomwe liri ndi tanthauzo lapadera, monga carat (^), chizindikiro cha dola ($) kapena asterisk (*).
Malingana ndi Linux, pali chiwerengero chokwanira cha ojambulawa ndipo matanthauzo awo amasiyana malingana ndi lamulo kapena pulogalamu yomwe mukuyendetsa.
Full Stop Monga Metacharacter (.)
Mzere wodzichepetsa umagwiritsidwa ntchito kupatsa malo omwe alipo pomwe mukugwiritsa ntchito malamulo monga cd , kupeza kapena sh koma muzinthu zofunikira monga awk , grep ndi sed izo amagwiritsidwa ntchito kutanthauzira aliyense.
Mwachitsanzo, lamulo lotsatira lidzapeza ma fayilo onse a fayilo panopa ndi pansipa.
pezani. -name * .mp3
Ngati mutayendetsa lamuloli mumalangizo anu ogwira ntchito (pwd) ndiye kuti mutha kupeza zotsatira zowonjezera, mukuganiza kuti mumasunga fayilo zanu mu nyimbo mu foda yanu.
Tsopano taonani lamulo ili:
ps -ef | Dulani f_efox
Masalimo a ps imatchula njira zonse zomwe zimagwirira ntchito pa kompyuta yanu. Malemba a grep amatenga mizere yowonjezera ndi kufufuza kachitidwe.
Choncho, ps-fe command imapeza mndandanda wa njira zogwiritsira ntchito ndipo zimapereka kwa grep yomwe imayang'ana mzere uliwonse mndandanda umene uli ndi fefox pomwe. angatanthauze khalidwe lililonse.
Ngati muli ndi firefox ikuyendetsani mudzapeza machesi. Mofananamo, ngati muli ndi pulogalamu yotchedwa fonefox kapena freefox yothamanga idzabwezeretsanso.
Thesterisk monga metacharacter (*)
The asterisk ndi metacharacter yodziŵika kwambiri padziko lonse ndipo amagwiritsidwa ntchito kutanthawuza 0 kapena kuposerapo pofufuza chitsanzo.
Mwachitsanzo:
pezani. -name * .mp3
The * .mp3 imabweretsanso machesi a fayilo iliyonse imene imatha mu .mp3. Mofananamo, ndikanatha kugwiritsa ntchito asterisk ndi lamulo la grep monga izi zikuwonetsera:
ps -ef | grep F * efox
Tiyenera kuzindikira kuti izi zimasiyana pang'ono chifukwa asterisk amatanthauza zero kapena zambiri komanso kupeza firefox, facefox ndi fonefox zingapezenso flutefox, ferretfox ngakhale fefox.
Carat Monga Metacharacter (^)
Carat (^) imagwiritsidwa ntchito kutanthauza kuyamba kwa mzere kapena chingwe. Ndiye amagwiritsidwa ntchito motani?
Ls command imagwiritsidwa ntchito kulemba mafayilo onse mu foda monga:
ls
Ngati mukufuna kudziwa mafayilo onse mu foda yomwe imayamba ndi chingwe china monga "gnome" ndiye carat ingagwiritsidwe ntchito kutchulidwa chingwe.
Mwachitsanzo:
ls | tcherani
Onani kuti izi zikungosonyeza ma fayilo omwe amayamba ndi zochepa. Ngati mukufuna maofesi omwe ali ndi dzina lopanda dzina paliponse ndiye kuti mubwereranso ku asterisk.
Chitsanzo cha pamwambapa, ls amabweretsanso mndandanda wa ma fayilo ndi mapepala omwe amalemba zolemba zomwe zimagwiritsidwa ntchito pofanana. grep amadziwa kuti chizindikiro cha carat chimatanthauza kupeza chirichonse chomwe chimayambira ndi anthu omwe amatsatira pambuyo pake ndipo panopa, ndi zochepa.
Chizindikiro cha Dollar Monga Metacharacter ($)
Chizindikiro cha dola chingakhale ndi matanthauzo ambiri monga metacharacter mkati mwa Linux.
Pogwiritsidwa ntchito pofananitsa zitsanzo zimatanthauza zosiyana ndi carat ndipo imatanthawuza njira iliyonse yomwe imatha ndi chingwe.
Mwachitsanzo:
ls | grep png $
Izi zikulemba mafayilo onse omwe amatha ndi png.
Chizindikiro cha dola chimagwiritsidwanso ntchito poyang'ana zochitika zachilengedwe mkati mwa chipolopolo cha bash.
Mwachitsanzo:
galu kutumiza = molly
limbani imbwa $
Galu lolanditsa katundu = molly limapanga kusinthasintha kwa chilengedwe chotchedwa galu ndikuyika mtengo wake ku molly. Kufikira chilengedwe chimasinthidwa $ symbol imagwiritsidwa ntchito. Ndalamayi imasonyeza chizindikiro cha mbwa imasonyeza molly koma popanda izo, mawu a galu amangoonetsa mawu agalu.
Kuthawa Metacharacters
Nthawi zina simukufuna kuti metacharacter ikhale ndi tanthauzo lapadera. Bwanji ngati muli ndi fayilo yotchedwa f.refox ndi fayilo yotchedwa firefox.
Tsopano yang'anani pa lamulo lotsatira:
ls | grep f.refox
Mukuganiza kuti mukubwezeredwa chiyani? Zonse f.refox ndi firefox zimabweretsedwa chifukwa zonsezi zimagwirizana ndi chitsanzocho.
Kuti mubwerere f.refox mungathe kuthawa kuyima kwathunthu kuti muyimire kuima kwathunthu motere:
ls | grep f \\
Anthu Amadzimadzi Omwe Amagwira Ntchito Ndiponso Zomwe Amanena
| Makhalidwe | Meaning |
| . | Chikhalidwe chilichonse |
| * | Zero kapena zolemba zambiri |
| ^ | Lembani mzere uliwonse kapena chingwe chomwe chimayambira ndi chitsanzo (mwachitsanzo ^ chochepa) |
| $ | Lembani mzere uliwonse kapena chingwe chomwe chimatha ndi chitsanzo (mwachitsanzo, ndalama zopanda malire) |
| \ \ | Amathawa chikhalidwe chotsatira kuchotsa tanthauzo lake lapadera |
| [] | Lembani mndandanda umodzi kapena mndandanda (mwachitsanzo ["abc", "def"] kapena [1..9] |
| + | Gwirizanitsani chimodzi kapena zingapo zisanayambe (mwachitsanzo grep a) |
| ? | Zero zofanana kapena imodzi yapitayi |