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(string errorMessage, string LogFilePath)

{

FileInfo oFileInfo = new FileInfo(LogFilePath);

DirectoryInfo oDirInfo = new DirectoryInfo(oFileInfo.DirectoryName);


if(!oDirInfo.Exists)

oDirInfo.Create();

if(!oFileInfo.Exists)

oFileInfo.Create();

StreamWriter w = File.AppendText(LogFilePath);

w.Write("\r\nLog Entry : ");

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

DateTime.Now.ToLongDateString());

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.

 

[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

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]
- (e-mail address removed)

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(string errorMessage, string LogFilePath)

{

FileInfo oFileInfo = new FileInfo(LogFilePath);

DirectoryInfo oDirInfo = new DirectoryInfo(oFileInfo.DirectoryName);


if(!oDirInfo.Exists)

oDirInfo.Create();

if(!oFileInfo.Exists)

oFileInfo.Create();

StreamWriter w = File.AppendText(LogFilePath);

w.Write("\r\nLog Entry : ");

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

DateTime.Now.ToLongDateString());

w.WriteLine(" :");

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

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

// Update the underlying file.

w.Flush();

// Close

w.Close();

}