[Freedos-devel] File directory buffering and updates
I have a report from a user who is getting stale directory data when running the mTCP FTP server. They are running a TSR in the background which is updating a file once a day. If they connect to the FTP server and look at the directory they will see the date and size of the file at the time the FTP server started, not the most current values. Apparently a WATTCP32 based app has the same symptoms, but the Datalight Sockets FTP server does not. (I think the Datalight Sockets FTP server runs as a TSR, not a foreground app.) I use _dos_findfirst and _dos_findnext to read directories. These use function 0x4E. I expect that if there is a TSR modifying something in the background that calling the DOS function directly (as I am) should provide the most current results, but that is not what is being reported. Can somebody give me an idea of what I am missing? I am not sure what they would get if they tried to open the file and transfer it. I also don't know if the TSR is closing the file after each update - I imagine that leaving the file open would create problems. Regards, Mike -- All of the data generated in your IT infrastructure is seriously valuable. Why? It contains a definitive record of application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-d2d-c2 ___ Freedos-devel mailing list Freedos-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-devel
Re: [Freedos-devel] File directory buffering and updates
Interesting ... but lacks details. AFAIK DOS has no good multitasking design so you can't do reliably file I/O (even more writes) from a TSR. - file not closed after update ? - file updated using lower level sector access ? - updating of the file fails while your FTP server is runnig (check after exit) ? - FreeDOS vs EDR-DOS ? What does the TSR do ? Of course you could add a feature into your FTP server at given time to automatically suspend, spawn some other app (updating the files), and then continue. Alternatively, define a "communication block" in memory, the TSR will write it's wishes into this block only, and your FTP server will execute them on files (rename, append data, replace data, kick file, ...). -- BlackBerry® DevCon Americas, Oct. 18-20, San Francisco, CA The must-attend event for mobile developers. Connect with experts. Get tools for creating Super Apps. See the latest technologies. Sessions, hands-on labs, demos & much more. Register early & save! http://p.sf.net/sfu/rim-blackberry-1 ___ Freedos-devel mailing list Freedos-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-devel
