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Writeascripttocreatamenuusingcase?

Postedby:informaticareferenceon:12/29/2011

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$vimenu_case.shcleartputcut1025echomainmenutputcut1125echotputcut1225echo1.Datetputcut1325echo2.Allfilestputcut1325echo3.AllUserstputcut1425echo4.Noitemsfoundreadchoicecase$choicein1)echoTodayDate::`date`;;2)lsf;;3)finger;;*)exit;;esac:wq



Writeascripttocheckthegiventypeofcharacter?



$vichar_type.shechoenteracharacterreadcharcase$charin[az])echolowercase;;[AZ])echouppercase;;[09])echoDigit;;?)echospecialcharacter;;*)echoEnteredmorethanonecharacter;;esac:wq

Writeascripttocheckthegiventwofileareequalornot?



$vitwofiles_same.shechoenterfirstfilereadf1echoentersecondfilereadf2x=`cmp$f1$f2`if[z$x]thenechobotharesameelseechobotharenotsamefi:wq



Writeascriptopenthegivenfile?



$viopen_file.shechoenterfilename:readfnameif[e$fname]thenif[f$fname]thenif[r$fname]thencat$fnameelsechmodu+r$fnamecat$fnameelseitisnotaregularfileelseechoItisnotaregualrfileelseechofiledoesntexistfi:wq

Writeascripttocheckthegiventypeoffile?



$vitype_file.shechoenterfilename:readfnameif[e$fname]thenif[f$fname]thenechoregularfileelseechodirectoryfileelif[l$fname]then



echolinkfileelif[b$fnameoc$fname]thenechoDevicefilefi:wq

Writeascripttocheckthegivenuserisloggedinornot?



$videlete.shechoenterloginname:readlnameifwho|grep$lname>/dev/nullthenechouserisonlineelseechouserisofflinefi:wq

Writeascripttodeletethegivenfile?



$videlete.shechoenterfilename:readfnameifrm$fnamethenechodeletedthefileelseechofileisnotexistedfi:wq



Writeascripttoaccepttwostringsandcheckthegivenstringsareequalornot?



$vitwo_strings.shechoenterfirststring:reads1echoentersecondstring:reads2if[$s1=$s2]thenechoequalelseechonotequalfi:wq

Writeascripttocheckthegivennumberisevenoroddnumber?



$vieven_odd.shechoenteranumber:readnif[`expr$n%2`=0]thenechoenterednumber:evennumberelseechoenterednumber:oddnumberfi:wq

Writeascripttocheckthegivnnumberispositiveornegative?





$vipos_neg.shechoenteranumber:readnif[$ngt0]thenechoenterednumber:positivenumberelseechoenterednumber:negativenumberfi:wq

Writeascripttodeleteduplicatelinesfromafile?



$viduplicate.shechoenterafilenametodeletereadfnamesort$fname|uniqueu>tempmvtemp$fnameechofilewithuniquelinescat$fname:wq

Writeascripttodeletetheblanklines?



$viblank_lines.shechoenterafilenametodeletereadfnamegrepv^$$fname>tempmvtemp$fnameechoafterdeletingthelinescat$fname:wq



Writeashellscripttoopenagivenfile?



$viopen.shechoenterafilenametoopenreadfnamecat$fname:wq

**Howtoexcutreshellscript?$./open.shor$shopen.sh

UnixInterviewQuestionsPart1



1.Howtodisplaythe10thlineofafile?head10filename|tail1

2.Howtoremovetheheaderfromafile?sedi1dfilename

3.Howtoremovethefooterfromafile?sedi$dfilename

4.Writeacommandtofindthelengthofalineinafile?Thebelowcommandcanbeusedtogetalinefromafile.sednpfilenameWewillseehowtofindthelengthof10thlineinafilesedn10pfilename|wcc

5.HowtogetthenthwordofalineinUnix?cutfd

6.Howtoreverseastringinunix?echojava|rev

7.HowtogetthelastwordfromalineinUnixfile?echounixisgood|rev|cutf1d|rev

8.HowtoreplacethenthlineinafilewithanewlineinUnix?



8.HowtoreplacethenthlineinafilewithanewlineinUnix?sedi10dfilename#dstandsfordeletesedi10inewinsertedlinefilename#istandsforinsert

9.HowtocheckifthelastcommandwassuccessfulinUnix?echo$?

10.Writecommandtolistallthelinksfromadirectory?lslrt|grep^l

11.HowwillyoufindwhichoperatingsystemyoursystemisrunningoninUNIX?unamea

12.Createareadonlyfileinyourhomedirectory?touchfile;chmod400file

13.HowdoyouseecommandlinehistoryinUNIX?Thehistorycommandcanbeusedtogetthelistofcommandsthatweareexecuted.

14.Howtodisplaythefirst20linesofafile?Bydefault,theheadcommanddisplaysthefirst10linesfromafile.Ifwechangetheoptionofhead,thenwecandisplayasmanylinesaswewant.head20filenameAnalternativesolutionisusingthesedcommandsed21,$dfilenameThedoptionheredeletesthelinesfrom21totheendofthefile

15.Writeacommandtoprintthelastlineofafile?Thetailcommandcanbeusedtodisplaythelastlinesfromafile.tail1filenameAlternativesolutionsare:sedn$pfilenameawkEND{print$0}filename

Refer:http://www.folkstalk.com/2011/11/topunixinterviewquestionspart1.html

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