rsync - Oct 2016 - -e escape rule

> Yeah, it only does space-splitting and that's all it will ever do. It
still looks to me like there is a bug in the original escaping, since any
command receiving that string is receiving a backslash that is not supposed to
be there. It should only be escaping the string enough to get it to rsync, not
trying to guess what rsync is going to do with it after it gets it.
I'm not proposing some additional characters to split on, but quite
the opposite, to handle the backslash escaped spaces correctly and NOT
split. Rest assured, there is no bug with the original escaping. For
your edification:

$ echo \I\'\m\ \a\ \s\t\r\i\n\g
I'm a string

On Sat 29 Oct 2016, Samuel Williams wrote:
> I'm not proposing some additional characters to split on, but quite
> the opposite, to handle the backslash escaped spaces correctly and NOT
> split. Rest assured, there is no bug with the original escaping. For
> your edification:
> 
> $ echo \I\'\m\ \a\ \s\t\r\i\n\g
> I'm a string
The point is that the original escaping DOUBLE escapes an equals sign:
 foo\\\=bar
It shouldn't, there's no reason to.


Paul

> The point is that the original escaping DOUBLE escapes an equals sign:
> foo\\\=bar
> It shouldn't, there's no reason to.
If you paste into your command line:

rsync -e ssh\ -l\ backup\ -i\ /etc/synco/id_rsa\ -o\
ConnectTimeout\\\=60\ -o\ BatchMode\\\=yes

The list of arguments would be (i.e. the values in ARGV):

['rsync', '-e', 'ssh -l backup -i /etc/synco/id_rsa -o
ConnectTimeout\=60 -o BatchMode\=yes']

The command

ssh -l backup -i /etc/synco/id_rsa -o ConnectTimeout\=60 -o BatchMode\=yes

Is a correct and valid shell command.

When RSync parses this in do_cmd, it should convert the '\=` sequence
into '=' but it doesn't.. This intuition is derived from the fact
that
if you instead passed the string to `system('ssh -l backup -i
/etc/synco/id_rsa -o ConnectTimeout\=60 -o BatchMode\=yes')` that the
ARGV generated would be ['ssh', '-l', 'backup',
'-i',
'/etc/synco/id_rsa', '-o', 'ConnectTimeout=60',
'-o',
'BatchMode=yes'].

Basically, even if there WAS no reason to do so, doesn't mean it's
invalid or undesirable. In theory, even passing in -e \\s\\s\\h should
be valid.

On 30 October 2016 at 01:13, Paul Slootman <paul+rsync at wurtel.net>
wrote:
> On Sat 29 Oct 2016, Samuel Williams wrote:
>
>> I'm not proposing some additional characters to split on, but quite
>> the opposite, to handle the backslash escaped spaces correctly and NOT
>> split. Rest assured, there is no bug with the original escaping. For
>> your edification:
>>
>> $ echo \I\'\m\ \a\ \s\t\r\i\n\g
>> I'm a string
>
> The point is that the original escaping DOUBLE escapes an equals sign:
>  foo\\\=bar
> It shouldn't, there's no reason to.
>
>
> Paul
>
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