Re: [lazarus] Detect if file is written?
Alexandre Leclerc wrote: Hi all, an application writes a text file on disk (Windows) and my FPC application opens it to process it. On some systems I open the file faster than the OS has finished writing it. I then get an 'Unexpected end of file'. I would like to know if there is a way I can detect the file is finish written on the disk; else should I simply trap the error and then close/reopen if I get it? Regards. Other solution is to change this application which writes to text file on disk,that way that it should write to temporary file and then change filename to destination.Because renaming file is atomic under linux and windows you will not worry about file writes. Regards Boguslaw _ To unsubscribe: mail [EMAIL PROTECTED] with "unsubscribe" as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
AW: [lazarus] Detect if file is written?
>I think the problem is with the write cache. The system don't write >data to disk directly, but to a cache, and when it has time, it >writes 'really' to the disk. Don't know on windows, but on unix >system the system call is flush. No, the write cache is also readed by the system so it schoudnt be a problem i think. Christian _ To unsubscribe: mail [EMAIL PROTECTED] with "unsubscribe" as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Detect if file is written?
At 20:34 14/08/2006, you wrote: Hi all, an application writes a text file on disk (Windows) and my FPC application opens it to process it. On some systems I open the file faster than the OS has finished writing it. I then get an 'Unexpected end of file'. I would like to know if there is a way I can detect the file is finish written on the disk; else should I simply trap the error and then close/reopen if I get it? I think the problem is with the write cache. The system don't write data to disk directly, but to a cache, and when it has time, it writes 'really' to the disk. Don't know on windows, but on unix system the system call is flush. HTH _ To unsubscribe: mail [EMAIL PROTECTED] with "unsubscribe" as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Detect if file is written?
Can you make a program to lock file that is written ? If so, then all you should check is that the file is unlocked... But still remember that the data can be problematic ... Another way is to monitor file for changes... I'd seen few Delphi applications that does that, but I do not remember any specific program. Anyway you can also do a monitor of your own like so: changes of file size ... for example check 3 times and see the file size changes, and then wait for a second and check 3 times again ... Repeat it until file size was not changed for more then 3/6 checks ... Ido On 8/14/06, Christian U. <[EMAIL PROTECTED]> wrote: try except end; :) when an exception occours it is not finished !? not very "clean" but i think the only way to detect this good Christian - Original Message - From: "Alexandre Leclerc" <[EMAIL PROTECTED]> To: "lazarus mailinglist" Sent: Monday, August 14, 2006 8:34 PM Subject: [lazarus] Detect if file is written? > Hi all, > > an application writes a text file on disk (Windows) and my FPC > application opens it to process it. On some systems I open the file > faster than the OS has finished writing it. I then get an 'Unexpected > end of file'. > > I would like to know if there is a way I can detect the file is finish > written on the disk; else should I simply trap the error and then > close/reopen if I get it? > > Regards. > > -- > Alexandre Leclerc > > _ > To unsubscribe: mail [EMAIL PROTECTED] with > "unsubscribe" as the Subject >archives at http://www.lazarus.freepascal.org/mailarchives > > > _ To unsubscribe: mail [EMAIL PROTECTED] with "unsubscribe" as the Subject archives at http://www.lazarus.freepascal.org/mailarchives _ To unsubscribe: mail [EMAIL PROTECTED] with "unsubscribe" as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Detect if file is written?
try except end; :) when an exception occours it is not finished !? not very "clean" but i think the only way to detect this good Christian - Original Message - From: "Alexandre Leclerc" <[EMAIL PROTECTED]> To: "lazarus mailinglist" Sent: Monday, August 14, 2006 8:34 PM Subject: [lazarus] Detect if file is written? > Hi all, > > an application writes a text file on disk (Windows) and my FPC > application opens it to process it. On some systems I open the file > faster than the OS has finished writing it. I then get an 'Unexpected > end of file'. > > I would like to know if there is a way I can detect the file is finish > written on the disk; else should I simply trap the error and then > close/reopen if I get it? > > Regards. > > -- > Alexandre Leclerc > > _ > To unsubscribe: mail [EMAIL PROTECTED] with > "unsubscribe" as the Subject >archives at http://www.lazarus.freepascal.org/mailarchives > > > _ To unsubscribe: mail [EMAIL PROTECTED] with "unsubscribe" as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
[lazarus] Detect if file is written?
Hi all, an application writes a text file on disk (Windows) and my FPC application opens it to process it. On some systems I open the file faster than the OS has finished writing it. I then get an 'Unexpected end of file'. I would like to know if there is a way I can detect the file is finish written on the disk; else should I simply trap the error and then close/reopen if I get it? Regards. -- Alexandre Leclerc _ To unsubscribe: mail [EMAIL PROTECTED] with "unsubscribe" as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
