Re: Identifying End of Tx in FTP

[Adam Shostack <adam () homeport org>]

Laris Benkis wrote:
| We have a system in place where clients drop off files via FTP to a
| wu-ftp server which are then processed automatically by scripts. Files
| have to be processed relatively quickly for the application to work
| properly therefore the convention we have developed is to indicate end
| of transmission by doing a rename of the file once the initial put is done. 
| We are trying to tighten the security of the whole process and want to
| use FW1 ftp resources to limit where puts can be done.  Unfortunately it
| turns out that when the ftp resources are used it is no longer possible to
| do rename.  

| What is a reliable, transparent way to tell that an ftp transmission has
| been completed?

        Depending on the OS, open(file, O_EXLOCK, mode) might work.

        You can also look at using lsof (ls open files) to see what
files are open, or looking at the wu-ftp process to see what files it
has open.  (If your system has a /proc/$PID/fd/ type structure this
could be very easy.)

Adam



-- 
"It is seldom that liberty of any kind is lost all at once."
                                                       -Hume