[Richard Sharpe <sharpe@xxxxxxxxxx>]

Hi,

Attached is a PERL script that builds a prototype dissector.

If we suggets that people who write dissectors use this to generate their
initial dissector, we have a number of advantages ...

BTW, it is uuencoded ...

begin 766 build-dissector.pl
M(R$O=7-R+V)I;B]P97)L"B,@0G5I;&0@=&AE('-K96QA=&]N(&]F(&$@9&ES
M<V5C=&]R("XN+@HC"B,@5V4@=V]U;&0@86-C97!T('-O;64@9FQA9W,@979E
M;G1U86QL>2P@8G5T(&9O<B!N;W<@=V4@86-C97!T(&]N92!A<F=U;65N="`*
M(R!T:&%T(&=I=F5S('1H92!N86UE(&]F('1H92!D:7-S96-T;W(*(PID:64@
M(EEO=2!M=7-T('-P96-I9GD@=&AE(&YA;64@;V8@82!D:7-S96-T;W(A(B!U
M;FQE<W,@*"0C05)'5B`^/3`I.PH*(R!(;6UM+"!W92!S:&]U;&0@8VAE8VL@
M=VAE=&AE<B!O<B!N;W0@<W5C:"!A(&1I<W-E8W1O<B!E>&ES=',_"@IP<FEN
M="`B0W)E871I;F<@82!D:7-S96-T;W(@<VME;&%T;VX@9F]R('1H92`D05)'
M5ELP72!P<F]T;V-O;%QN(CL*"F1I92`B0V]U;&0@;F]T(&]P96X@<VME;&%T
M;VX@9FEL93H@)#\B('5N;&5S<R!O<&5N($]55"P@(CXN+W!A8VME="TD05)'
M5ELP72YC+G-K96PB.PH*<')I;G0@3U54("(O*B!P86-K970M)$%21U9;,%TN
M8UQN(B`N"B(@*B!2;W5T:6YE<R!F;W(@)$%21U9;,%T@<&%C:V5T(&1I<V%S
M<V5M8FQY7&XB("X*(B`J7&XB("X*(B`J(%PD260Z(%PD7&XB("X*(B`J(%QN
M(B`N"B(@*B!#;W!Y<FEG:'0@*&,I(#(P,#`@8GD@64]54B!.04U%($A%4D4@
M/%E/55(@14U!24P@2$5213Y<;B(@+@HB("I<;B(@+@HB("H@171H97)E86P@
M+2!.971W;W)K('1R869F:6,@86YA;'EZ97)<;B(@+@HB("H@0GD@1V5R86QD
M($-O;6)S7&XB("X*(B`J($-O<'ER:6=H="`Q.3DY($=E<F%L9"!#;VUB<UQN
M(B`N"B(@*B!4:&ES('!R;V=R86T@:7,@9G)E92!S;V9T=V%R93L@>6]U(&-A
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M;VXN7&XB("X*(B`J7&XB("X*(B`J(%1H:7,@<')O9W)A;2!I<R!D:7-T<FEB
M=71E9"!I;B!T:&4@:&]P92!T:&%T(&ET('=I;&P@8F4@=7-E9G5L+%QN(B`N
M"B(@*B!B=70@5TE42$]55"!!3ED@5T%24D%.5%D[('=I=&AO=70@979E;B!T
M:&4@:6UP;&EE9"!W87)R86YT>2!O9EQN(B`N"B(@*B!-15)#2$%.5$%"24Q)
M5%D@;W(@1DE43D534R!&3U(@02!005)424-53$%2(%!54E!/4T4N("!3964@
M=&AE7&XB("X*(B`J($=.52!'96YE<F%L(%!U8FQI8R!,:6-E;G-E(&9O<B!M
M;W)E(&1E=&%I;',N7&XB("X*(B`J7&XB("X*(B`J(%EO=2!S:&]U;&0@:&%V
M92!R96-E:79E9"!A(&-O<'D@;V8@=&AE($=.52!'96YE<F%L(%!U8FQI8R!,
M:6-E;G-E7&XB+@HB("H@86QO;F<@=VET:"!T:&ES('!R;V=R86T[(&EF(&YO
M="P@=W)I=&4@=&\@=&AE($9R964@4V]F='=A<F5<;B(@+@HB("H@1F]U;F1A
M=&EO;BP@26YC+BP@-3D@5&5M<&QE(%!L86-E("T@4W5I=&4@,S,P+"!";W-T
M;VXL($U!("`P,C$Q,2TQ,S`W+"!54T$N7&XB("X*(B`J+UQN(B`N"B)<;B(@
M+@HB(VEF9&5F($A!5D5?0T].1DE'7TA<;B(@+@HB(VEN8VQU9&4@7")C;VYF
M:6<N:%PB7&XB("X*(B-E;F1I9EQN(B`N"B)<;B(@+@HB(VEF9&5F($A!5D5?
M4UE37U194$537TA<;B(@+@HB(R!I;F-L=61E(#QS>7,O='EP97,N:#Y<;B(@
M+@HB(V5N9&EF7&XB("X*(EQN(B`N"B(C:69D968@2$%615].151)3D547TE.
M7TA<;B(@+@HB(VEN8VQU9&4@/&YE=&EN970O:6XN:#Y<;B(@+@HB(V5N9&EF
M7&XB("X*(EQN(B`N"B(C:6YC;'5D92`\<W1D:6\N:#Y<;B(@+@HB(VEN8VQU
M9&4@/'-T9&QI8BYH/EQN(B`N"B(C:6YC;'5D92`\8W1Y<&4N:#Y<;B(@+@HB
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M="YH7")<;B(@+@HB(VEN8VQU9&4@7")R97-O;'8N:%PB7&XB("X*(B-I;F-L
M=61E(%PB<')E9G,N:%PB7&XB("X*(EQN(B`N"B(O*B-D969I;F4@5$-07U!/
M4E1?(B`N('5C*"1!4D=66S!=*2`N("(@/%-/344@4$]25"!.54U"15(^*B]<
M;B(@+@HB=F]I9"!P<F]T;U]R96=?:&%N9&]F9E\D05)'5ELP72AV;VED*3M<
M;B(@+@HB7&XB("X*(G-T871I8R!I;G0@<')O=&]?)$%21U9;,%T@/2`M,3M<
M;B(@+@HB7&XB("X*(B\J($1E;&5T92!T:&4@9F]L;&]W:6YG(&EF('EO=2!D
M;R!N;W0@=7-E(&ET+"!O<B!A9&0@=&\@:70@:68@>6]U(&YE960@*B]<;B(@
M+@HB<W1A=&EC(&EN="!H9E\D05)'5ELP75]R97$@/2`M,3M<;B(@+@HB<W1A
M=&EC(&EN="!H9E\D05)'5ELP75]R<W`@/2`M,3M<;B(@+@HB7&XB("X*(G-T
M871I8R!I;G0@971T7R1!4D=66S!=(#T@+3$[7&XB("X*(EQN(B`N"B)S=&%T
M:6,@:6YT('1C<%]P;W)T(#T@,#M<;EQN7&XB.PH*<')I;G0@3U54("(O*B!!
M9&0@>6]U<B!F=6YC=&EO;G,@:&5R92`J+UQN7&XB.PH*<')I;G0@3U54(")S
M=&%T:6,@:6YT(&=L;V)A;%\D05)'5ELP75]T8W!?<&]R="`](%1#4%]03U)4
M7R(@+B!U8R@D05)'5ELP72D@+B`B.UQN(B`N"B)<;B(@+@HB(VEF(#!<;B(@
M+@HB<W1A=&EC('9O:61<;B(@+@HB9&ES<V5C=%\D05)'5ELP72AT=F)U9F9?
M="`J='9B+"!P86-K971?:6YF;R`J<&EN9F\L('!R;W1O7W1R964@*G1R964I
M7&XB("X*(GM<;B(@+@HB(V5L<V5<;B(@+@HB<W1A=&EC('9O:61<;B(@+@HB
M9&ES<V5C=%\D05)'5ELP72AC;VYS="!U7V-H87(@*G!D+"!I;G0@;V9F<V5T
M+"!F<F%M95]D871A("IF9"Q<;B(@+@HB"0D@('!R;W1O7W1R964@*G1R964I
M7&XB("X*(EQN(B`N"B)[7&XB("X*(B`@='9B=69F7W0@("`@("`@*G1V8B`]
M('1V8E]C<F5A=&5?9G)O;5]T;W`H;V9F<V5T*3M<;B(@+@HB("!P86-K971?
M:6YF;R`@("`J<&EN9F\@/2`F<&D[7&XB("X*(B-E;F1I9EQN(B`N"B(@('!R
M;W1O7W1R964@("`@("HD05)'5ELP75]T<F5E+"`J=&D[7&XB.PH*<')I;G0@
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M;G0@3U54("(C:68@,%QN(B`N"B(@($-(14-+7T1)4U!,05E?05-?1$%402AP
M<F]T;U\D05)'5ELP72P@='9B+"!P:6YF;RP@=')E92D[7&XB("X*(B-E;'-E
M7&XB("X*(B`@3TQ$7T-(14-+7T1)4U!,05E?05-?1$%402AP<F]T;U\D05)'
M5ELP72P@<&0L(&]F9G-E="P@9F0L('1R964I.UQN(B`N"B(C96YD:69<;EQN
M(CL*"G!R:6YT($]55"`B+RH@061D('EO=7(@9&ES<V5C=&EO;B!C;V1E(&AE
M<F4@*B]<;EQN(CL*"G!R:6YT($]55"`B("!I9B`H8VAE8VM?8V]L*&9D+"!#
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M;B(@+@HB("!I9B`H8VAE8VM?8V]L*&9D+"!#3TQ?24Y&3RDI('L@("\J($-H
M96-K('1H92!T>7!E("XN+B`J+UQN(B`N"B)<;B(@+@HB("`@(&-O;%]A9&1?
M9G-T<BAF9"P@0T],7TE.1D\L(%PB)7-<(BP@9F]R;6%T7W1E>'0H8VUD+"!%
M3D1?3T9?1E)!344I*3M<;B(@+@HB7&XB("X*(B`@?5QN(B`N"B)<;B(@+@HB
M("!I9B`H=')E92D@>R`@+RH@0G5I;&0@=&AE('1R964@:6YF;R`N+BX@*B]<
M;EQN(CL*"B(@("`@=&D@/2!P<F]T;U]T<F5E7V%D9%]I=&5M*'1R964L('!R
M;W1O7R1!4D=66S!=+"!.=6QL5%9"+"!O9F9S970L($5.1%]/1E]&4D%-12P@
M1D%,4T4I.UQN(B`N"B(@("`@)$%21U9;,%U?=')E92`]('!R;W1O7VET96U?
M861D7W-U8G1R964H=&DL(&5T=%\D05)'5ELP72D[7&XB("X*"G!R:6YT($]5
M5"`B+RH@061D('EO=7(@9&ES<V5C=&EO;B!C;V1E(&AE<F4@=&\@8G5I;&0@
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M"B(@('-T871I8R!H9E]R96=I<W1E<E]I;F9O(&AF6UT@/2![7&XB("X*(B`@
M("![("9H9E\D05)'5ELP75]R97$L7&XB("X*(B`@("`@("\J($-H86YG92!T
M:&4@9F]L;&]W:6YG('1O('1H92!T>7!E('EO=2!N965D("HO7&XB("X*(B`@
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M04XL($)!4T5?3D].12P@3E5,3"P@,'@P+"!<(EPB('U]+%QN(B`N"B)<;B(@
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M<W!O;G-E7"(L(%PB)$%21U9;,%TN<G-P7"(L($947T)/3TQ%04XL($)!4T5?
M3D].12P@3E5,3"P@,'@P+"!<(EPB('U]+%QN(B`N"B)<;B(@+@HB("`@("\J
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M("X*(EQN(B`N"B(@('U<;B(@+@HB("!E;'-E('M<;B(@+@HB7&XB("X*(B`@
M("`D05)'5ELP75]P<F5F<U]I;FET:6%L:7IE9"`](%12544[7&XB("X*(EQN
M(B`N"B(@('U<;B(@+@HB7&XB("X*(B`@+RH@4V5T(&]U<B!P;W)T(&YU;6)E
M<B!F;W(@9G5T=7)E('5S92`J+UQN(B`N"B)<;B(@+@HB("!T8W!?<&]R="`]
M(&=L;V)A;%\D05)'5ELP75]T8W!?<&]R=#M<;B(@+@HB7&XB("X*(B`@;VQD
M7V1I<W-E8W1O<E]A9&0H7")T8W`N<&]R=%PB+"!G;&]B86Q?)$%21U9;,%U?
M=&-P7W!O<G0L(&1I<W-E8W1?)$%21U9;,%TI.UQN(B`N"B)<;B(@+@HB?5QN
%7&XB.PH`
`
end


Regards
-------
Richard Sharpe, sharpe@xxxxxxxxxx
Samba (Team member, www.samba.org), Ethereal (Team member, www.zing.org)
Contributing author, SAMS Teach Yourself Samba in 24 Hours
Author, Special Edition, Using Samba