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[REBOL] Re: noob question -- insert 2 byte hexidecimal value into binary string

From: tomc:cs:uoregon at: 14-Apr-2008 14:25

Sorry I need to actually read your question. Tom Conlin wrote:
> hi Doug > > search for url-encode on rebol.org > you will get some old examples that should still work > > here is one > > http://www.rebol.org/cgi-bin/cgiwrap/rebol/view-script.r?script=cookies-client.r > > DougEdmunds wrote: > >> I am building a binary string, composed of >> 1) some hex code >> 2) the length of a string (as 2 bytes in hex16) >> 3) the string >> >> Without the length of the string in the middle, it looks like this: >> >> >> join #{836B} "Fred Flintstone and Wilma Flintstone" >> == #{ >> 836B4672656420466C696E7473746F6E6520616E642057696C6D6120466C696E >> 7473746F6E65 >> } >> >> I need to insert the length of the string as a >> two byte heximdecimal value after the initial #{836B} >> and before the string-as-hex part. >> >> >> length? "Fred Flintstone and Wilma Flintstone" >> == 36 >> >> What I need is a 2 byte representation of the length (#0024), >> inserted so the finished binary is: >> >> #{ >> 836B00244672656420466C696E7473746F6E6520616E642057696C6D6120466C696E >> 7473746F6E65} >> >> >> I can get a 2 byte representation in hex of the length: >> >> >> to-hex length? "Fred Flintstone and Wilma Flintstone" >> == #00000024 >> >> >> remove/part to-hex length? "Fred Flintstone and Wilma Flintstone" 4 >> == #0024 >> >> But if I try to join it with the first part, it gets converted to ascii >> first. >> >> >> x: remove/part to-hex length? "Fred Flintstone and Wilma Flintstone" 4 >> == #0024 >> >> y: #{836B} >> == #{836B} >> >> >> join y x >> == #{836B30303234} ; no good >> >> If someone can show me how to do this, much appreciated. >> >> == Doug Edmunds >> >> >> >> >
-- ... nice weather eh tomc-cs.uoregon.edu