Multithreading

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   If this library tread safe? I am using the library in a windows service (C#) where I can have multiple threads that create/update pdf documents.  

Don't see any problems so far. Should I expect any?

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alecd4 Members Profile Find Members Posts Beginner Joined: 29 Sep 11 Status: Offline Points: 10	Post Options Post Reply Quote alecd4 Report Post Thanks(0) Quote Reply Topic: Multithreading Posted: 21 Apr 12 at 10:47PM
	If this library tread safe? I am using the library in a windows service (C#) where I can have multiple threads that create/update pdf documents. Don't see any problems so far. Should I expect any?

AndrewC Members Profile Find Members Posts Moderator Group Joined: 08 Dec 10 Location: Geelong, Aust Status: Offline Points: 841	Post Options Post Reply Quote AndrewC Report Post Thanks(0) Quote Reply Posted: 26 Apr 12 at 1:14PM
	Running QPL in a service could be a problem because we use GDI+ for many PDF functions. From http://msdn.microsoft.com/en-us/library/ms533798(v=vs.85).aspx "GDI+ functions and classes are not supported for use within a Windows service. Attempting to use these functions and classes from a Windows service may produce unexpected problems, such as diminished service performance and run-time exceptions or errors."

Wheeley Members Profile Find Members Posts Senior Member Joined: 30 Oct 05 Location: United States Status: Offline Points: 146	Post Options Post Reply Quote Wheeley Report Post Thanks(0) Quote Reply Posted: 26 Apr 12 at 11:32PM
	Do you have a list of these functions? My company is using it in a service and so far we have not had any problems. But I'd like to very for sure we wouldn't. Wheeley

AndrewC Members Profile Find Members Posts Moderator Group Joined: 08 Dec 10 Location: Geelong, Aust Status: Offline Points: 841	Post Options Post Reply Quote AndrewC Report Post Thanks(0) Quote Reply Posted: 30 Apr 12 at 3:24PM
	We haven't done any testing with using QPL in a Windows Service. The GDI+ function calls in QPL are used for the Rendering and Printing functions. Wheeley - Which QPL calls do you currently use in your Windows Service ? This might help us and others work out which functions, if any, are unsafe to use in a Windows Service ?

AndrewC Members Profile Find Members Posts Moderator Group Joined: 08 Dec 10 Location: Geelong, Aust Status: Offline Points: 841	Post Options Post Reply Quote AndrewC Report Post Thanks(0) Quote Reply Posted: 30 Apr 12 at 4:09PM
	Also, we have recently completed more extensive testing on the library for thread safety and have found a few small problems that have been fixed in the 8.15 release and there are further fixes coming for the 8.16 beta 1 release. If each thread uses a new instance of QuickPDF Library then it should work pretty well when using 8.15 or 8.16 versions of QPL.

Wheeley Members Profile Find Members Posts Senior Member Joined: 30 Oct 05 Location: United States Status: Offline Points: 146	Post Options Post Reply Quote Wheeley Report Post Thanks(0) Quote Reply Posted: 30 Apr 12 at 11:49PM
	We use the following when running in a service: AddToFileList AnalyseFile ClearFileList CompressContent CreateLibrary Decrypt DecryptFile DeleteAnalysis DocumentCount EncodePermissions EncryptFile EncryptionStatus FileListItem GetAnalysisInfo GetDocumentID LastErrorCode LibraryVersion LoadFromFile MergeFileListFast NewDocument NewOutline PageCount PrintDocument PrintOptions RemoveDocument SaveToFile SelectDocument SelectPage SetPageLayout SetPageMode SetTempFile SetTempPath SignFile TestTempPath Unlock UnlockKey Wheeley

AndrewC Members Profile Find Members Posts Moderator Group Joined: 08 Dec 10 Location: Geelong, Aust Status: Offline Points: 841	Post Options Post Reply Quote AndrewC Report Post Thanks(0) Quote Reply Posted: 02 May 12 at 3:38PM
	Wheely, PrintDocument uses the GDI+ functions to render the document for printing. If it is working correctly for you then it seems Microsoft might are just being over cautious. Not of the other functions you use would require GDI+. Andrew.

Wheeley Members Profile Find Members Posts Senior Member Joined: 30 Oct 05 Location: United States Status: Offline Points: 146	Post Options Post Reply Quote Wheeley Report Post Thanks(0) Quote Reply Posted: 02 May 12 at 8:42PM
	The catch with the function using GDI+ is how you run your service. Microsoft might indeed be correct when you run the service using "Local Administrator". Because of other issues we require our service to run using a named user. So more investigation is needed by all. Wheeley