<html><head><base href="x-msg://6/"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><br></div>- Create and open a file with a temporary name.<div>- Write the file content.<div>- Close the file.</div><div>- Rename the file to the name/place you want.</div><div><br></div><div>works ?</div><div> </div><div>/Tony</div><div><br><div><div><div><div>On 7 mar 2012, at 18:25, David Mercer wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div lang="EN-US" link="blue" vlink="purple"><div class="WordSection1" style="page: WordSection1; "><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; ">While this isn’t an Erlang-specific question, the problem arises from my using Richard Carlsson’s<span class="Apple-converted-space"> </span><i>file_monitor</i>(<a href="https://github.com/richcarl/eunit/blob/master/src/file_monitor.erl" style="color: blue; text-decoration: underline; ">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></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; "><o:p> </o:p></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; ">I had thought that by doing a<span class="Apple-converted-space"> </span><span style="font-family: Consolas; ">file:open(Filepath, [read])</span><span class="Apple-converted-space"> </span>and making sure I got back<span class="Apple-converted-space"> </span><span style="font-family: Consolas; ">{ok, _}</span><span class="Apple-converted-space"> </span>rather than<span style="font-family: Consolas; ">{error, eacces}</span><span class="Apple-converted-space"> </span>I could avoid those cases, but that approach has failed for me: this morning, I got back<span class="Apple-converted-space"> </span><span style="font-family: Consolas; ">{ok, _}</span>, but the file was not completely written yet.<o:p></o:p></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; "><o:p> </o:p></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; ">Another approach I tried was to attempt to obtain an exclusive lock (I think it was<span class="Apple-converted-space"> </span><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></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; "><o:p> </o:p></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; ">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 class="Apple-converted-space"> </span><span style="font-family: Consolas; ">file:open(Filepath, [read])</span><span class="Apple-converted-space"> </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></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; "><o:p> </o:p></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; ">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></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; "><o:p> </o:p></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; ">Cheers,<o:p></o:p></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; "><o:p> </o:p></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; ">David Mercer<o:p></o:p></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; "><o:p> </o:p></div><div style="margin-top: 0in; margin-right: 0in; margin-left: 0in; margin-bottom: 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif; "><o:p> </o:p></div></div>_______________________________________________<br>erlang-questions mailing list<br><a href="mailto:erlang-questions@erlang.org" style="color: blue; text-decoration: underline; ">erlang-questions@erlang.org</a><br><a href="http://erlang.org/mailman/listinfo/erlang-questions" style="color: blue; text-decoration: underline; ">http://erlang.org/mailman/listinfo/erlang-questions</a><br></div></span></blockquote></div><br><div>
<span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div><span class="Apple-style-span" style="color: rgb(51, 51, 51); font-family: Geneva, Arial, Helvetica, sans-serif; font-size: 12px; ">"Installing applications can lead to corruption over time. </span><span class="Apple-style-span" style="color: rgb(51, 51, 51); font-family: Geneva, Arial, Helvetica, sans-serif; font-size: 12px; ">Applications gradually write over each other's libraries, partial upgrades occur, user and system errors happen, and minute changes may be unnoticeable and difficult to fix"</span></div><div><span class="Apple-style-span" style="color: rgb(51, 51, 51); font-family: Geneva, Arial, Helvetica, sans-serif; font-size: 12px; "><br></span></div></span><br class="Apple-interchange-newline">
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