Re: Silent change to string.pack("cn",...) between 5.3.1 and 5.3.2

[Sam Chang <sam.chang@...>]

lua string is more like char buffer, it can contains more \0 in it, so if you want to compare two string as the `common string`, just compare them after a simple trim.

> On Apr 8, 2016, at 12:19, Duane Leslie <parakleta@darkreality.org> wrote:
> 
>> On 7 April 2016 at 13:34, Duane Leslie <parakleta@darkreality.org> wrote:
>>> LUA_PACKPADBYTE (not necessarily '\0')
>>> 
>>> The padding option is definitely convenient but I dislike padding with LUA_PACKPADBYTE rather than '\0'
>> 
>> LUA_PACKPADBYTE *is* defined as '\0'.
>> If you're defining it to something else, don't complain that it's different....
> 
> My issue is not so much what it may or may not be defined as, but
> rather that semantically it is not the same as '\0' and this has the
> flow on effect that when it is silently inserted by `pack()` it is
> then loudly returned by `unpack()`.
> 
> In all other cases `unpack()` swallows any LUA_PACKPADBYTE but it
> cannot in the case of the fixed string format because it allows any
> data to be inserted and so cannot differentiate padding bytes from
> legitimate data.  If you pad the zero terminated string with '\0' then
> you can remove them when unpacking because the semantics are clear.
> 
> Regards,
> 
> Duane.
>