[REBOL] noob question -- insert 2 byte hexidecimal value into binary string
From: dougedmunds:gmai:l at: 14-Apr-2008 14:07
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
