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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>While this isn’t an Erlang-specific question, the problem arises from my using Richard Carlsson’s <i>file_monitor</i> (<a href="https://github.com/richcarl/eunit/blob/master/src/file_monitor.erl">https://github.com/richcarl/eunit/blob/master/src/file_monitor.erl</a>), which sends messages when a file or directory is changed. I have found that it is not unusual to get a message about a new file before the file has been completely written.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I had thought that by doing a <span style='font-family:Consolas'>file:open(Filepath, [read])</span> and making sure I got back <span style='font-family:Consolas'>{ok, _}</span> rather than <span style='font-family:Consolas'>{error, eacces}</span> I could avoid those cases, but that approach has failed for me: this morning, I got back <span style='font-family:Consolas'>{ok, _}</span>, but the file was not completely written yet.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Another approach I tried was to attempt to obtain an exclusive lock (I think it was <span style='font-family:Consolas'>file:open(Filepath, [read, exclusive])</span>), but in my testing I came across the bizarre scenario where I would copy a file into the monitored directory, the file_monitor would send the message, but the Erlang process that does the file-open didn’t see it, so created the file (the documentation says it creates the file if it does not exist), and then I got a message in my window where I was copying that the file already exists, do I want to overwrite it.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Another approach I tried was renaming the file to itself. All my tests indicated that that approach would work, but all my tests also indicated that just doing the <span style='font-family:Consolas'>file:open(Filepath, [read])</span> would work, too, so I chose it, as it seemed cleaner. I could revert to the rename approach, but I’m not even sure now that that will work.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I imagine others among us have encountered this issue, and rather than reinvent the wheel, what is the favored approach to handling this issue?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Cheers,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>David Mercer<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>