Kuv yuav ua li cas thiaj li tau txais 100 kab kawg ntawm cov ntaub ntawv hauv Unix?
Tus Tsov tus tw hais kom ua yog ib qho kev siv hluav taws xob rau kev tso tawm qhov kawg ntawm cov ntaub ntawv muab rau nws ntawm tus qauv nkag. Nws sau cov txiaj ntsig mus rau cov qauv tsim tawm. Los ntawm lub neej ntawd tus Tsov tus tw rov qab kaum kab kawg ntawm txhua cov ntaub ntawv uas nws tau muab. Nws kuj tseem siv tau los ua raws cov ntaub ntawv hauv lub sijhawm tiag tiag thiab saib raws li cov kab tshiab tau sau rau nws.
Kuv yuav pom 10 kab kawg ntawm cov ntaub ntawv hauv Unix li cas?
Linux tail command syntax
Tail yog ib qho lus txib uas luam tawm ob peb kab kawg (10 kab los ntawm lub neej ntawd) ntawm qee cov ntaub ntawv, ces xaus. Piv txwv 1: Los ntawm lub neej ntawd "tail" luam tawm 10 kab kawg ntawm cov ntaub ntawv, ces tawm. raws li koj tuaj yeem pom, qhov no luam tawm 10 kab kawg ntawm /var/log/messages.
Koj nyeem thawj 100 kab ntawm cov ntaub ntawv hauv Unix li cas?
Ntaus lub taub hau hauv qab no kom pom thawj 10 kab ntawm cov ntaub ntawv hu ua "bar.txt":
- taub hau -10 bar.txt.
- taub hau -20 bar.txt.
- sed -n 1,10p /etc/group.
- sed -n 1,20p /etc/group.
- awk 'FNR <= 10' /etc/passwd.
- awk 'FNR <= 20' /etc/passwd.
- perl -ne'1..10 and print' /etc/passwd.
- perl -ne'1..20 and print' /etc/passwd.
18 xee. Xyoo 2018.
Kuv yuav ua li cas thiaj li tau txais 50 kab kawg hauv Linux?
Tus Tsov tus tw hais kom ua, los ntawm lub neej ntawd, 10 kab kawg ntawm cov ntawv nyeem hauv Linux. Cov lus txib no tuaj yeem pab tau zoo thaum kuaj xyuas cov haujlwm tsis ntev los no hauv cov ntaub ntawv teev cia. Hauv daim duab saum toj no koj tuaj yeem pom tias 10 kab kawg ntawm /var/log/messages file tau tshwm sim. Lwm qhov kev xaiv uas koj yuav pom tau yooj yim yog qhov kev xaiv -f.
Dab tsi yog txheej txheem los suav cov cim thiab kab hauv cov ntaub ntawv?
Cov lus txib "wc" feem ntau txhais tau tias "cov lus suav" thiab nrog cov kev xaiv sib txawv ib tus tuaj yeem siv nws los suav cov kab, cov lus, thiab cov cim hauv cov ntawv nyeem. Siv wc tsis muaj kev xaiv yuav ua rau koj suav ntawm bytes, kab, thiab cov lus (-c, -l thiab -w xaiv).
Cov lus txib twg yog siv los sib piv cov ntaub ntawv?
Cov lus txib twg yog siv los tso saib qhov sib txawv ntawm cov ntaub ntawv? Kev piav qhia: diff hais kom ua yog siv los sib piv cov ntaub ntawv thiab qhia qhov sib txawv ntawm lawv.
Yuav ua li cas koj grep thawj 10 kab?
taub hau -n10 filename | grep ... lub taub hau yuav tso tawm thawj 10 kab (siv qhov kev xaiv -n), thiab tom qab ntawd koj tuaj yeem tso cov yeeb nkab tso tawm rau grep . Koj tuaj yeem siv cov kab hauv qab no: taub hau -n 10 /path/to/file | grep […]
Kuv yuav qhia cov kab ntawv hauv Unix li cas?
lwm yam khoom
- awk : $>awk '{if(NR==LINE_NUMBER) print $0}' file.txt.
- sed : $>sed -n LINE_NUMBERp file.txt.
- head : $>head -n LINE_NUMBER file.txt | tail -n + LINE_NUMBER Ntawm no LINE_NUMBER yog, kab xov tooj twg koj xav luam tawm. Piv txwv: Sau ib kab los ntawm ib daim ntawv.
26 xee. Xyoo 2017.
Kuv yuav grep kab kawg ntawm cov ntaub ntawv li cas?
Koj tuaj yeem kho qhov no ua ib lub rooj, nyob rau hauv uas thawj kab yog lub npe cov ntaub ntawv thiab qhov thib ob yog qhov sib tw, qhov twg cov kab sib cais yog ':' tus cwj pwm. Tau kab kawg ntawm txhua cov ntaub ntawv (prefixed nrog cov ntaub ntawv npe). Tom qab ntawd, lim cov zis raws li tus qauv. Lwm txoj hauv kev rau qhov no tuaj yeem ua nrog awk tsis yog grep.
Kuv yuav luam thawj 10 cov ntaub ntawv hauv UNIX li cas?
Luam thawj n cov ntaub ntawv los ntawm ib phau ntawv mus rau lwm qhov
- nrhiav. – maxdepth 1 -type f | taub hau -5 | xargs cp -t /target/directory. Qhov no zoo li pheej hmoo, tab sis ua tsis tiav vim hais tias osx cp tsis tshwm sim kom muaj. -t hloov.
- exec nyob rau hauv ob peb txawv configurations. Qhov no tej zaum ua tsis tiav rau cov teeb meem syntax ntawm kuv kawg : / Kuv tsis tuaj yeem zoo li tau txais lub taub hau xaiv ua haujlwm.
13 xee. Xyoo 2018.
Koj nyeem thawj kab ntawm cov ntaub ntawv hauv plhaub ntawv li cas?
Txhawm rau khaws cov kab nws tus kheej, siv var = $ (command) syntax. Hauv qhov no, line=$(awk 'NR==1 {print; exit}' file). Nrog cov kab sib npaug = $(sed -n '1p' file). yuav marginally sai dua li nyeem yog ib tug built-in bash hais kom ua.
Tus miv hais kom ua dab tsi?
'miv' [luv luv rau "concatenate"] cov lus txib yog ib qho ntawm cov lus txib uas nquag siv hauv Linux thiab lwm lub tshuab ua haujlwm. Cov lus txib miv tso cai rau peb los tsim ib lossis ntau cov ntaub ntawv, saib muaj cov ntaub ntawv, sib txuas cov ntaub ntawv thiab redirect tso zis hauv davhlau ya nyob twg lossis cov ntaub ntawv.
Koj ua li cas tso saib 5 kab kawg ntawm cov ntaub ntawv hauv Unix?
taub hau -15 /etc/passwd
Txhawm rau saib ob peb kab kawg ntawm cov ntaub ntawv, siv tus Tsov tus tw hais kom ua. tus Tsov tus tw ua haujlwm tib yam li lub taub hau: ntaus tus Tsov tus tw thiab lub npe file kom pom 10 kab kawg ntawm cov ntaub ntawv ntawd, lossis ntaus tus Tsov tus tw -number filename kom pom cov kab kawg ntawm cov ntaub ntawv. Sim siv tus Tsov tus tw los saib tsib kab kawg ntawm koj .
Kuv yuav luam cov kab kawg N hauv Linux li cas?
1. suav cov kab hauv cov ntaub ntawv, siv 'cat f. txt | wc -l` thiab tom qab ntawd siv lub taub hau thiab tus Tsov tus tw hauv lub raj xa dej los luam tawm 81424 kab kawg ntawm cov ntaub ntawv (kab #totallines-81424-1 rau #totallines).
Koj ua li cas txuas ntxiv tail ib cov ntaub ntawv hauv Linux?
Tus Tsov tus hais kom ua yog ceev thiab yooj yim. Tab sis yog tias koj xav tau ntau dua li ua raws li cov ntaub ntawv (piv txwv li, scrolling thiab tshawb nrhiav), ces tsawg dua yuav yog cov lus txib rau koj. Nias Shift-F. Qhov no yuav coj koj mus rau qhov kawg ntawm cov ntaub ntawv, thiab tsis tu ncua tso saib cov ntsiab lus tshiab.