Re: Proxy support for zftp functions

[Peter Stephenson <pws@cambridgesiliconradio.com>]

> The main use for it is to be able to compare times on remote/local
> files. Without it no real directory sync (and even reliable reget) is
> possible. Is it possible to pass file date/size from function to zftp.c
> code? O.K., file mtime can be set by function as well ...

Checking the time is is only ever done in the shell code; checking the size
is only done by C for passing down to zftp_progress for info, so the only
reason for using C code at all would be to make parsing easier.

But it's certainly not a trivial problem to compare two dates from shell
code, because the information about time zones is hard to get at --- for
exactly that reason, the zftp functions call perl to do it for them (see
the function zfrtime).  I don't have a simple answer to this, but a date
and time parsing and conversion module might be a nice extension --- or, of
course, a piece of shell code that does it neatly, if that's possible.

Come to think of it, there's a hack using the stat module for local files.
% touch foo; stat -s +mtime foo; stat -g +mtime foo
Mon May 22 17:59:38
Mon May 22 16:59:38

(Unfortunately you only get it as text, since the time in seconds since the
epoch is always in GMT.)

And how do you get the GMT modification time for a remote file reliably if
you can't rely on MDTM, anyway?
-- 
Peter Stephenson <pws@cambridgesiliconradio.com>
Cambridge Silicon Radio, Unit 300, Science Park, Milton Road,
Cambridge, CB4 0XL, UK                          Tel: +44 (0)1223 392070