Yadda ake karanta shigarwar Awk daga STDIN a cikin Linux - Kashi na 7

A cikin ɓangarorin da suka gabata na jerin kayan aikin Awk, mun kalli shigarwar karanta galibi daga fayil (s), amma menene idan kuna son karanta labari daga STDIN.

A cikin wannan Sashe na 7 na jerin Awk, za mu kalli ƴan misalan inda za ku iya tace fitar wasu umarni maimakon karanta labari daga fayil.

Za mu fara da umarnin ls, a misali na farko da ke ƙasa, muna amfani da fitarwa na dir -l umarni a matsayin shigarwa ga Awk don buga sunan mai amfani, sunan rukuni da fayilolin da ya mallaka a halin yanzu. directory:

# dir -l | awk '{print $3, $4, $9;}'

Dubi wani misali inda muke amfani da maganganun awk, anan, muna son buga fayilolin mallakar tushen mai amfani ta amfani da magana don tace kirtani kamar a cikin umarnin awk da ke ƙasa:

# dir -l | awk '$3=="root" {print $1,$3,$4, $9;} '

Umurnin da ke sama ya haɗa da ma'aikacin kwatance (==) don taimaka mana wajen tace fayiloli a cikin kundin adireshi na yanzu waɗanda tushen mai amfani ya mallaka. Ana samun wannan ta amfani da kalmar $3==”tushen”.

Bari mu kalli wani misali na inda muke amfani da ma'aikacin kwatancen awk don dacewa da takamaiman kirtani.

Anan, mun yi amfani da mai amfani don duba abubuwan da ke cikin fayil mai suna tecmint_deals.txt kuma muna son duba ma'amalar nau'in Tech kawai, don haka za mu aiwatar da umarni masu zuwa:

# cat tecmint_deals.txt
# cat tecmint_deals.txt | awk '$4 ~ /tech/{print}'
# cat tecmint_deals.txt | awk '$4 ~ /Tech/{print}'

A cikin misalin da ke sama, mun yi amfani da ƙimar ~/tsari/ ma'aikacin kwatance, amma akwai umarni guda biyu don gwada fitar da wani abu mai mahimmanci.

Lokacin da kuke gudanar da umarni tare da fasahar ƙirar babu abin da aka buga saboda babu wata yarjejeniya irin wannan, amma tare da Tech, kuna samun nau'ikan nau'ikan Tech.

Don haka a koyaushe a kula yayin amfani da wannan ma'aikacin kwatanta, yana da mahimmanci kamar yadda muka gani a sama.

Kuna iya amfani da fitarwa na wani umarni koyaushe a matsayin shigarwa don awk maimakon karanta shigarwar daga fayil, wannan abu ne mai sauƙi kamar yadda muka duba a cikin misalan da ke sama.

Da fatan misalan sun bayyana sarai don ku fahimta, idan kuna da wata damuwa, zaku iya bayyana su ta sashin sharhin da ke ƙasa kuma ku tuna don duba sashe na gaba na jerin inda za mu kalli fasali mai ban tsoro kamar masu canji, lambobi da lambobi da ƙari. masu gudanar da ayyuka.