How to handling the file concurrency issue?

[Mullin Yu]

I create a component to write the error log as follow, but it seems
sometimes locked by other processes, and pop up the I/O exception.

How can we handling the concurrency issue at file level? Retry accessing the
file if catch error => like waiting and polling.

Thanks!

private void LogError2File(s tring errorMessage, string LogFilePath)

{

FileInfo oFileInfo = new FileInfo(LogFil ePath);

DirectoryInfo oDirInfo = new DirectoryInfo(o FileInfo.Direct oryName);
if(!oDirInfo.Ex ists)

oDirInfo.Create ();

if(!oFileInfo.E xists)

oFileInfo.Creat e();

StreamWriter w = File.AppendText (LogFilePath);

w.Write("\r\nLo g Entry : ");

w.WriteLine("{0 } {1}", DateTime.Now.To LongTimeString( ),

DateTime.Now.To LongDateString( ));

w.WriteLine(" :");

w.WriteLine(" :{0}", errorMessage);

w.WriteLine
("----------------------------------------------------------------");

// Update the underlying file.

w.Flush();

// Close

w.Close();

}

[Nicholas Paldino [.NET/C# MVP]]

Mullin,

Instead of calling AppendText, open the FileStream yourself, allowing it
to be shared for read-only access, but you maintain the write access.

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard. caspershouse.co m

"Mullin Yu" <mu*******@ctil .com> wrote in message
news:%2******** ********@TK2MSF TNGP10.phx.gbl. ..

I create a component to write the error log as follow, but it seems
sometimes locked by other processes, and pop up the I/O exception.

How can we handling the concurrency issue at file level? Retry accessing the file if catch error => like waiting and polling.

Thanks!

private void LogError2File(s tring errorMessage, string LogFilePath)

{

FileInfo oFileInfo = new FileInfo(LogFil ePath);

DirectoryInfo oDirInfo = new DirectoryInfo(o FileInfo.Direct oryName);
if(!oDirInfo.Ex ists)

oDirInfo.Create ();

if(!oFileInfo.E xists)

oFileInfo.Creat e();

StreamWriter w = File.AppendText (LogFilePath);

w.Write("\r\nLo g Entry : ");

w.WriteLine("{0 } {1}", DateTime.Now.To LongTimeString( ),

DateTime.Now.To LongDateString( ));

w.WriteLine(" :");

w.WriteLine(" :{0}", errorMessage);

w.WriteLine
("----------------------------------------------------------------");

// Update the underlying file.

w.Flush();

// Close

w.Close();

}

[Mullin Yu]

do i need to implement any multiple-producer-consumer pattern at this case?

more than one process/application will write to the error log file.

what's the implementation of commercial software then? like iis log, tomcat
log?

thanks!

regards,
mullin

"Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard .caspershouse.c om> wrote in
message news:up******** ******@TK2MSFTN GP09.phx.gbl...

Mullin,

Instead of calling AppendText, open the FileStream yourself, allowing it to be shared for read-only access, but you maintain the write access.

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard. caspershouse.co m

"Mullin Yu" <mu*******@ctil .com> wrote in message
news:%2******** ********@TK2MSF TNGP10.phx.gbl. ..

I create a component to write the error log as follow, but it seems
sometimes locked by other processes, and pop up the I/O exception.

How can we handling the concurrency issue at file level? Retry accessing

the

file if catch error => like waiting and polling.

Thanks!

private void LogError2File(s tring errorMessage, string LogFilePath)

{

FileInfo oFileInfo = new FileInfo(LogFil ePath);

DirectoryInfo oDirInfo = new DirectoryInfo(o FileInfo.Direct oryName);
if(!oDirInfo.Ex ists)

oDirInfo.Create ();

if(!oFileInfo.E xists)

oFileInfo.Creat e();

StreamWriter w = File.AppendText (LogFilePath);

w.Write("\r\nLo g Entry : ");

w.WriteLine("{0 } {1}", DateTime.Now.To LongTimeString( ),

DateTime.Now.To LongDateString( ));

w.WriteLine(" :");

w.WriteLine(" :{0}", errorMessage);

w.WriteLine
("----------------------------------------------------------------");

// Update the underlying file.

w.Flush();

// Close

w.Close();

}