Recognizing the Arrival of a New File

[Greg Lindstrom]

Hello-
I am writing an application where I need to recognize when a file
arrives in a given directory. Files may arrive at any time during the
course of the day. Do I set up a cron job to poll the directory every
few minutes? Write a daemon to monitor the directory? Or is there some
other more common/accepted way to perform this task? I'm using Python
2.3 on Linux.

Thanks for your help,
--greg

--
Greg Lindstrom 501 975.4859
Computer Programmer (e-mail address removed)
NovaSys Health
Little Rock, Arkansas

"We are the music makers, and we are the dreamers of dreams." W.W.

 

[Christos TZOTZIOY Georgiou]

I am writing an application where I need to recognize when a file
arrives in a given directory. Files may arrive at any time during the
course of the day. Do I set up a cron job to poll the directory every
few minutes? Write a daemon to monitor the directory? Or is there some
other more common/accepted way to perform this task? I'm using Python
2.3 on Linux.

The most common way to watch for a file or a directory change (in my experience)
is to use the SGI fam (file alteration monitor); I think it has been ported to
Linux. Otherwise, either way you describe is common use. Suggestion: first
check for changes in the st_mtime of the directory, then search for the file
existence.

 

[Chris Green]

Hello-
I am writing an application where I need to recognize when a file
arrives in a given directory. Files may arrive at any time during the
course of the day. Do I set up a cron job to poll the directory every
few minutes? Write a daemon to monitor the directory? Or is there some
other more common/accepted way to perform this task? I'm using Python
2.3 on Linux.

At my last job, we had a similar problem and I wanted to be able to
check that the file was closed by the application that was putting it
there (in that case the application was w32 writing to a share via
samba).

http://cmg.dok.org/cgi-bin/pyblosxom.cgi/python/linuxlease/

Every other way I could find that relied on simple FS semantics had
the possibility of reading a file partially.