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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: Counted strings
Date: Sat, 03 Dec 2016 18:57:27 -0800
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jacobnavia <jacob@jacob.remcomp.fr> writes:
> Instead of prefixing a string with its count, we could do a variable 
> length encoding, like in utf8.
>
> Strings of length 0 to 254 would be prefixed by a byte containing the 
> length. If the value of that byte is 255 (0xff, all ones) it means that 
> the length is encoded in the next two bytes.
>
> Those two bytes encode lengths from 255 to 65535-2, --> 65533. The 
> length is given by
>
> l == index - 1,
>
> i.e. if we read 576 from those two bytes, the real length of the 
> following data bytes is 575.
[...]

Another possibility is to start the array with a single UTF-8
encoded code point representing the length in bytes.  With standard
UTF-8 encoding this gives you lengths up to 2**21-1 in 4 bytes.
Extrapolating the scheme gives you up to 2**42-1 encoded in 8 bytes.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"