Parsing Program Arguments - Perl Cookbook [Book] - O'Reilly

Parsing Program Arguments Problem You want to let users change your program's behavior by giving options on the command line. For instance, you want to ... Skiptomaincontent PerlCookbookby GetfullaccesstoPerlCookbookand60K+othertitles,withfree10-daytrialofO'Reilly. There'salsoliveonlineevents,interactivecontent,certificationprepmaterials,andmore. Startyourfreetrial ParsingProgramArgumentsProblem Youwanttoletuserschangeyourprogram’sbehaviorbygiving optionsonthecommandline.Forinstance,youwanttoallowtheuser tocontrolthelevelofoutputthatyourprogramproduceswitha -v(verbose)option. SolutionUsethestandardGetopt::Stdmoduletopermitsingle-character options:useGetopt::Std; #-vARG,-DARG,-oARG,sets$opt_v,$opt_D,$opt_o getopt("vDo"); #-vARG,-DARG,-oARG,sets$args{v},$args{D},$args{o} getopt("vDo",\%args); getopts("vDo:");#-v,-D,-oARG,sets$opt_v,$opt_D,$opt_o getopts("vDo:",\%args);#-v,-D,-oARG,sets$args{v},$args{D},$args{o}Or,usethestandardGetopt::Longmoduletopermitnamed arguments:useGetopt::Long; GetOptions("verbose"=>\$verbose,#--verbose "Debug"=>\$debug,#--Debug "output=s"=>\$output);#--output=stringor--outputstringDiscussionMosttraditionalprogramslikelsand rmtakesingle-characteroptions(alsoknownas flagsorswitches),suchas-land -r.Inthecaseofls -landrm-r,theargumentis Boolean:eitheritispresentoritisn’t.Contrastthiswith gcc-ocompiledfilesource.c,where compiledfileisavalueassociatedwiththe option-o.WecancombineBoolean optionsintoasingleoptioninanyorder.Forexample:%rm-r-f/tmp/testdirAnotherwayofsayingthisis:%rm-rf/tmp/testdirTheGetopt::Stdmodule,partofthestandardPerldistribution, parsesthesetypesoftraditionaloptions.Its getopt functiontakesasinglestring... GetPerlCookbooknowwiththeO’Reillylearningplatform. O’Reillymembersexperienceliveonlinetraining,plusbooks,videos,anddigitalcontentfromnearly200publishers. Startyourfreetrial Don’tleaveempty-handed GetMarkRichards’sSoftwareArchitecturePatternsebooktobetterunderstandhowtodesigncomponents—andhowtheyshouldinteract. It’syours,free. Getitnow Close