I'm looking to create a baseline of file extensions and then search for the inverse of them (essentially scanning for new extensions and then reporting on them).I have:base_file=`find /volume1/ -type f | grep -E .*\.[a-zA-Z0-9]*$ | sed -e 's/.*\(\.[a-zA-Z0-9]*\)$/\1/' | sort | uniq -u`to create my baseline - the initial search of the files on the volume.For a small amount of files, using  find $dir -type f \( -not -name foo* -and -not -name *bar \) worked wonderfully.  Alas, I have tons of files, though.  If I pipe every unique extension into the find command, it does not work (understandably).  Ex. of output:.acx .adb .aex .agt .ahs .alt .amsorm .ANI .ARTX .ASAX .ASDefs .asmdot .ASMDOT .ASPX .atb .atm .aus .auth .authd .awk .ben .Bin .BIO .bkp .bms .boo .bootstrap .bplist .bridgesupport .bto .btt .CBK .ccp .cd .cdm .cdrom .CFGOLD .cfm .cfp .CFS .cg .cidb .cilk .clk .cmptag .CMValidateMovieDataReferenceService .ColorSyncXPCAgent .common .con .CONFIG .COR .cpi .cpu .crc .crdownload .crmlog .cryptodev .csh .ctd .ctl .cue .cws .d .daeexportpreset .daeimportpreset .DATA .dbg .DBG .dbl .DCD .DCX .debug .defaults .defltools .defmtools .der .desktop .dfont .DGDLL .DGN .DictionaryServiceHelper .dig .django .dla .dlb .dlh .dlk .dLL .dlmp .DLO .DMP .DNP .dps .DriverHelper .DRWDOT .dsd .dtc .DTL .dwd .dwfx .dwG .e .eai .eapol .EDB .edc .edited .ENC .eng .ENV .epub .erl .esi .esm .EVM .EVP .ews .example .exv .fac .fatal .fbk .FBK .fbT .FCL .fe .file .fin .fl .FLL .font .FontDownloadHelper .for .fpk .fre .frT .FW .FXP .gadget .Gadget .gdb .generic .ger .gi .glo .gm .gpx .groovy .group .gsl .gss .gws .GZ .ham .hbs .hd .hidden .hkf .hpdata .hs .htb .HTT .hun .hx .hxd .hxx .HXX .IBM .ICNS .igb .IGS .iHB .imaging .IME .IMG .in .INP .install .Installsettings .int .IPConfiguration .IPMonitor .ITK .ITS .iuf .java .jnilib .job .JPEG .jqx .kd .keychainproxy .keys .kondo .krn .kscript .ksh .lfs .libraries .LID .lisp .liveReg .local .LOCAL .lok .lppi .lsl .lt .ltools .mak .mako .mapping .mappings .mas .masm .matlab .mbr .mch .MDE .mdmp .mdw .me .med .MediaLibraryService .mem .mholders .MIF .MIG .min .mk .mm .mno .mobileconfig .mom .mp .MPE .mpq .MPV .mpx .MPX .msdb .MSDefs .msilog .MSM .MSP .mtools .mup .nasm .netsa .new .nfm .nlog .nor .nsi .ntd .numbers .nut .nv .nvv .NWD .O .oai .oct .Ocx .oft .ogv .older .omo .ooc .openAndSavePanelService .ori .orignal .osf .override .pad .page .partial .pas .patch .pbb .pch .Pdf .PDFFileRefsValidator .pdn .PDR .pexe .pfw .phar .pif .pike .pix .PJT .PJX .PLS .plsql .po .pokki .pot .ppf .ppk .pptm .preferences .PRG .prm .PRN .pro .propdesc .prtdot .PRTDOT .prx .PSDefs .PST .psw .pta .ptb .ptg .python .r .rayhosts .rc .rcd .RCF .rd .RecentPictureService .regcccc .registerassistantservice .RLA .rnd .rpk .RPW .RSC .rst .rupldb .rus .salog .sap .SAP .sbt .sbx .sbxx .SCH .schemas .scm .SCR .sct .SDP .sds .sdu .Search .securityd .SEP .set .setup .Setuplog .SFV .sfx .sgi .sgn .sidb .sidd .sigs .sites .skin .slddrt .smc .SMC .smf .smilebox .SOL .spdc .speechsynthesisd .spn .sqfs .squashfs .srt .srx .ssi .st .ste .stg .styx .swb .swtag .TAR .TDC .tdf .tex .th .tib .time .tips .tmx .tpg .tpm .trace .transformed .trm .TSK .tst .Txt .txz .type .udf .ufm .ult .uninstall .upd .upstart .urf .user .User .UserDictionary .UserProfile .UserScriptService .usr .ux .v .vala .values .var .VAR .vbe .VBR .vcs .vcxproj .vdb .vdf .VERSION .VersionsUIHelper .vhdl .vms .vmsn .vmss .VOL .voucher .vps .vsb .vst .vvv .wax .wbt .Wdf .webp .WIZ .wnt .WPT .ws .wsc .wsdl .WSF .wsp .xap .xht .XLL .xlS .XLT .xmp .xpfwext .xtext .yaml .zipx .zzHow can I search for all of these, or inverse of, without running into issues?  Or, more importantly, is there a better solution for this type of task?
Searching for a large number of extensions with find
files;find