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Download Embedded Linux Primer: A Practical, Real-World
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[28].debug_pubnamesPROGBITS0000000001e8c8001aae00001 [29].debug_infoPROGBITS00000000020376013d2700001 [30].debug_abbrevPROGBITS0000000003409d002ede00001 [31].debug_linePROGBITS00000000036f7b0034a200001 [32].debug_framePROGBITS0000000003a42000338000004 [33].debug_strPROGBITS0000000003d7a000067900001 [34].note.gnu.arm.ideNOTE0000000003de1900001c00001 [35].debug_rangesPROGBITS0000000003de3500001800001 [36].shstrtabSTRTAB0000000003de4d00018300001 [37].symtabSYMTAB0000000003e5e8004bd010387734 [38].strtabSTRTAB000000000431b80021bf00001 KeytoFlags: W(write),A(alloc),X(execute),M(merge),S(strings) I(info),L(linkorder),G(group),x(unknown) O(extraOSprocessingrequired)o(OSspecific),p(processorspecific) $ YoucanseefromListing15-1thattherearemanysectionscontainingdebuginformation.Thereis alsoa.commentsectionthatcontainsmorethan2KB(0x940)ofinformationthatisnotnecessaryfor theapplicationtofunction.Thesizeofthisexamplefile,includingdebuginformation,ismorethan 275KB. $ls-lwebsdemo -rwxrwxr-x1chrischris283511Nov818:48websdemo Ifwestripthisfileusingthestriputility,wecanminimizeitssizetopreserveresourcesonour targetsystem.Listing15-2showstheresults. Listing15-2.StripTargetApplication $xscale_be-strip-s-R.comment-owebsdemo-strippedwebsdemo $ls-lwebsdemo* -rwxrwxr-x1chrischris283491Apr909:19websdemo -rwxrwxr-x1chrischris123156Apr909:21websdemo-stripped $ Herewestripboththesymbolicdebuginformationandthe.commentsectionfromtheexecutable file.Wespecifythenameofthestrippedbinaryusingthe-ocommandlineswitch.Youcanseethat the resulting size of the stripped binary is less than half of its original size. Of course, for larger applications,thisspacesavingscanbeevenmoresignificant.ArecentLinuxkernelcompiledwith debuginformationwaslargerthan18MB.AfterstrippingasinListing15-2,theresultingbinarywas slightlylargerthan2MB! Fordebugginginthisfashion,youplacethestrippedversionofthebinaryonyourtargetsystem andkeepalocalunstrippedcopyonyourdevelopmentworkstationcontainingsymbolicinformation neededfordebugging.Youusegdbserveronyourtargetboardtoprovideaninterfacebacktoyour developmenthostwhereyourunthefull-blownversionofGDBonyournonstrippedbinary.
