From: Nate Eldredge <neldredge AT hmc DOT edu>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Detecting File in Use?
Date: 24 Apr 2001 16:31:25 -0700
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richard AT stardate DOT bc DOT ca (Richard Sanders) writes:

> >How does one know if a file is ALREADY in USE by
> >some application BEFORE any actual attempt to open
> >or access that file?
> 
> Check out the access(); function.  

That has nothing to do with it.

The correct answer is: you can't reliably find out.  lsof would tell
you whether the file was open, but that could change before you get
around to actually doing something with it.

If you need to enforce some kind of sharing between applications,
you'll need to use file locking in both of them.

-- 

Nate Eldredge
neldredge AT hmc DOT edu