<div class="gmail_quote">On Tue, Nov 3, 2009 at 20:49, Cameron Simpson <<a href="mailto:cs@zip.com.au">cs@zip.com.au</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> <div class="im">On 03Nov2009 13:31, Donald Russell <<a href="mailto:russell.don@gmail.com">russell.don@gmail.com</a>> wrote: | Another system uses FTP to drop files in a directory for me to process. | I have a bash script to process the incoming files. The script is started by | cron periodically. | | There's a problem if the FTP transfer is still in progress because the | process begins reading the file even though it isn't complete yet. </div>I liked the upload-then-rename suggested by another poster, if you can get this implemented. Otherwise... [...] <div class="im">| I could also configure the ftp server to lock files being written, but that | seems to be discouraged. (based on man vsftpd.conf) </div>It's not discouraged for any reason that seems to match your use case. You've got a well defined upload area and no malicious users. Use the lock facility! That's what it's for! <div class="im"> | Basically, what I want is something like | Can I get an exclusive read on file x? | No - skip that file, go onto the next one | Yes - start processing that file </div>Do it! See above! Have you tried it? Cheers, </blockquote></div> Thank you all for some great suggestions.... :-) Based on the feedback I've received, I'm going to ... 1 - configure vsftpd to lock files while writing (no malicious users etc) 2 - use ftp put/rename like put ftp-in-progress.foo.bar / rename ftp-in-progress.foo.bar foo.bar because it provides such a great "visual" for watchers, and a convenient way to determine which files are "in transit" and which are complete. 3 - use lockfile/fuser to ensure my cron job doesn't start processing a file that's already being read by an earlier cron job. Cheers