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• windows 7 64 bit visual studio 2008 libtiff build nmake error

  - by user1244539

  I am trying to build tiff 4.0.2 on my Windows 7 x64 system with Visual Studio 2008, but it was showing errors: C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2347) : error C2061: syntax error : identifier 'QINT' C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2362) : error C2059: syntax error : '}' C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2397) : error C2061: syntax error : identifier 'JOYCAPS' C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2397) : error C2059: syntax error : ';' C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2398) : error C2061: syntax error : identifier 'PJOYCAPS' C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2398) : error C2059: syntax error : ';' C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2399) : error C2061: syntax error : identifier 'NPJOYCAPS' C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2399) : error C2059: syntax error : ';' C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2400) : error C2061: syntax error : identifier 'LPJOYCAPS' C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2400) : error C2059: syntax error : ';' C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2534) : error C2146: syntax error : missing ')' before identifier 'pjc' C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2534) : error C2081: 'LPJOYCAPSA' : name in formal parameter list illegal C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2534) : error C2061: syntax error : identifier 'pjc' C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2534) : error C2059: syntax error : ';' C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2534) : error C2059: syntax error : ',' C:\Program Files\Microsoft SDKs\Windows\v6.0A\include\mmsystem.h(2534) : error C2059: syntax error : ')' NMAKE: fatal error u1077: "c:\program files(x86)\microsoft visual studio 9.0\vc\bin\cl.exe": return code '0x2' This is what I was doing: Extracted tiff 4.0.2 In VS 2008 x64 Win 7 command prompt setting the environment for x86 by running vcvars32.bat Changing the path to tiff 4.0.2/libtiff folder Running nmake /f makefile.vc to create a static library of libtiff Following these steps in Windows XP generates the .lib file but in Windows 7 it fails. This is the first time I'm making any .lib files.

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• web server response code 500

  - by Bryan Kemp

  I realize that this may spur a religious discussion, but I discussed this with friends and get great, but conflicting answers and the actual documentation is of little help. What does the 500 series response codes mean from the webserver? Internal Server Error, but that is vague. My assumption is that it means that something bad happened to the server (file system corruption, no connection to the database, network issue, etc.) but not specifically a data driven error (divide by zero, record missing, bad parameter, etc). Something to note, there are some web client implementations (the default Android and Blackberry httpclients) that do not allow access to the html boddy if the server response is 500 so there is no way to determine what caused the issue from the client. What I have been been implementing recently is a web service that returns a json payload wrapped in a response object that contains more specific error information if it is data related, but the server response will be 200 since it finished the actual processing. Thoughts?

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• Java Runtime Exec for VBA script with arguments

  - by Holograham

  I am trying to use Runtime exec() to run a vba script with arguements. I am having trouble passing in the args. I think I need to use the String[] overloaded method for exec. Currently this works: String command = "cmd /c \"\\concat2.vbs\"" Process p = Runtime.getRuntime().exec(command); But I want to run that with arguments and if I do this String command = "cmd /c \"\\concat2.vbs\" " + arg1 + " " + arg2 where arg1 and arg2 are strings my program doesnt run (status = 1)

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• how to redirect stdin to java Runtime.exec ?

  - by jprogram2010

  I want to execute some sql scripts using Java's Runtime.exec method. I intend to invoke mysql.exe / mysql.sh and redirect the script file to this process. From the command prompt I can run the command <mysqInstallDir\/bin\mysql.exe -u <userName> -p <password> < scripts\create_tables.sql I can invoke mysql.exe using Runtime.exec but how do I redirect data from sql file to mysql.exe ?

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• Setting ViewController delegates in iPhone runtime

  - by Stein Rune Risa

  I am writing an iPhone application and needed to use the address book functionality. For this to work, it is necessary to specify a ABPeoplePickerNavigationControllerDelegate on the ViewController. The problem is that I am creating all fields and buttons dynamically runtime, and thus does not have any custom ViewController - using only UIViewController class. My question is then - how can I specify the delegate runtime without having to create a ViewController class just for this purpose.

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• crude Runtime.exec to call java -cp not working in linux

  - by pstanton

  I'm using a java process to spawn many other java processes using Runtime.exec(cmd) where cmd is like the following: java -cp "MyJar.jar" pkg.MyClass some-more-arguments running the same command from the command line works fine in windows and linux, however when my spawning java process calls the command via Runtime.exec it works in windows but not in linux. in linux i get Exception in thread "main" java.lang.NoClassDefFoundError: pkg/MyClass any ideas?

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• Runtime C function details

  - by Sridhar

  Hi, Is there any way to find particular C language function's input and output parameters from a framework (apple's ARM) during the runtime or from any method with out knowing the headers. It is a framework and there are no header files for it.I decompile it with IDA Pro and it gives me the function names but not input and output parameters information. I am able to load those private functions using dlsym. Is it possible to find the parameters info in runtime (C language or Objective C) or from IDA Pro ? Regards, Raghu

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• Java - Runtime.getRuntime().exec() what's going on?

  - by kunkanwan

  Hi, I have problem with Runtime.exec() in Java My code: String lol = "/home/pc/example.txt"; String[] b = {"touch", lol}; try { Runtime.getRuntime().exec(b); } catch(Exception ex) { doSomething(ex); } It's working good but when I trying changle variable "lol" files doesn't create in hard disk for instance: String lol = x.getPath(); where getPath() returns String What should I do ? Thanks for your reply :)

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• How to resize controls at runtime in java

  - by user1349213

  Is there a way to resize a control, a JTextfield for example, at runtime in java? I want my textfield to have the resize cursors (just like when you point your cursor on the corner of a window) and will be able to resize on runtime. Ive read on the internet that vb6 and C# have those capabilities, is there anything for java? A sample code or a link to a good tutorial will be very much appreciated. Thank you.

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• PostGres Error When Using Distinct : postgres ERROR: could not identify an ordering operator for ty

  - by CaffeineIV

  ** EDIT ** Nevermind, just needed to take out the parens... I get this error: ERROR: could not identify an ordering operator for type record when trying to use DISTINCT Here's the query: select DISTINCT(g.fielda, g.fieldb, r.type) from fields g LEFT JOIN types r ON g.id = r.id; And the errors: ERROR: could not identify an ordering operator for type record HINT: Use an explicit ordering operator or modify the query. ********** Error ********** ERROR: could not identify an ordering operator for type record SQL state: 42883 Hint: Use an explicit ordering operator or modify the query.

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• Logging fatal/parse errors in PHP5

  - by PeterBelm

  I'm writing an error logging service that will be integrated into websites running on my server, that will email me error batches, etc. So I've been trying to find out if there's a way to handle fatal and parse errors, however not using the tricks to handle it in PHP code (output buffer, shutdown function). I'm quite happy to write some C code or something to handle it outside of my PHP code. I would also like to issue a redirect if possible (my sites use output buffering so there shouldn't be any headers sent). I'm pretty sure this could be done with a PHP module, but I've never written one and have no idea where to start.

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• ASP.NET Error Handling: Creating an extension method to send error email

  - by Jalpesh P. Vadgama

  Error handling in asp.net required to handle any kind of error occurred. We all are using that in one or another scenario. But some errors are there which will occur in some specific scenario in production environment in this case We can’t show our programming errors to the End user. So we are going to put a error page over there or whatever best suited as per our requirement. But as a programmer we should know that error so we can track the scenario and we can solve that error or can handle error. In this kind of situation an Error Email comes handy. Whenever any occurs in system it will going to send error in our email. Here I am going to write a extension method which will send errors in email. From asp.net 3.5 or higher version of .NET framework  its provides a unique way to extend your classes. Here you can fine more information about extension method. So lets create extension method via implementing a static class like following. I am going to use same code for sending email via my Gmail account from here. Following is code for that. using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Net.Mail; namespace Experiement { public static class MyExtension { public static void SendErrorEmail(this Exception ex) { MailMessage mailMessage = new MailMessage(new MailAddress("[email protected]") , new MailAddress("[email protected]")); mailMessage.Subject = "Exception Occured in your site"; mailMessage.IsBodyHtml = true; System.Text.StringBuilder errorMessage = new System.Text.StringBuilder(); errorMessage.AppendLine(string.Format("<B>{0}</B>:{1}<BR/>","Exception",ex.Message)); errorMessage.AppendLine(string.Format("<B>{0}</B>:{1}<BR/>", "Stack Trace", ex.StackTrace)); if (ex.InnerException != null) { errorMessage.AppendLine(string.Format("<B>{0}</B>:{1}<BR/>", " Inner Exception", ex.InnerException.Message)); errorMessage.AppendLine(string.Format("<B>{0}</B>:{1}<BR/>", "Inner Stack Trace", ex.InnerException.StackTrace)); } mailMessage.Body = errorMessage.ToString(); System.Net.NetworkCredential networkCredentials = new System.Net.NetworkCredential("[email protected]", "password"); SmtpClient smtpClient = new SmtpClient(); smtpClient.EnableSsl = true; smtpClient.UseDefaultCredentials = false; smtpClient.Credentials = networkCredentials; smtpClient.Host = "smtp.gmail.com"; smtpClient.Port = 587; smtpClient.Send(mailMessage); } } } After creating an extension method let us that extension method to handle error like following in page load event of page. using System; namespace Experiement { public partial class WebForm1 : System.Web.UI.Page { protected void Page_Load(object sender,System.EventArgs e) { try { throw new Exception("My custom Exception"); } catch (Exception ex) { ex.SendErrorEmail(); Response.Write(ex.Message); } } } } Now in above code I have generated custom exception for example but in production It can be any Exception. And you can see I have use ex.SendErrorEmail() function in catch block to send email. That’s it.. Now it will throw exception and you will email in your email box like below.   That’s its. It’s so simple…Stay tuned for more.. Happy programming.. Technorati Tags: Exception,Extension Mehtod,Error Handling,ASP.NET

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• Runtime binding of XML Schema to Java code

  - by Yaneeve

  Hi all, The situation is thus: I have an application which provides editing capabilities to XML an file. This file follows a certain Schema. The Schema belongs to a subset of Schemas which actually follow a line of evolution from one to another - so they are not so different from one another. The main difference between the schemas is an enumeration of string labels. I now have need to save "meta data" in XML format (This is a second type of XML file). This "meta data" contains a list of labels from the set enumerated in the schema. The application can accept a new schema at runtime and adjust itself. Therefore I have an XML file that must be validated by two schemas one static containing the basic structure of the "meta data" stored in the XML and one which contains the 'proper' label enumeration. The latter schema is determined at runtime. I have glanced over JAXB, XMLBeans and JiBX. I can't figure out what technology to choose that would allow for a runtime bind of code and schema in the way that would most benefit my use-case. Any suggestions? Thanks!

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• Error logging in C#

  - by rschuler

  I am making my switch from coding in C++ to C#. I need to replace my C++ error logging/reporting macro system with something similar in C#. In my C++ source I can write LOGERR("Some error"); or LOGERR("Error with inputs %s and %d", stringvar, intvar); The macro & supporting library code then passes the (possibly varargs) formatted message into a database along with the source file, source line, user name, and time. The same data is also stuffed into a data structure for later reporting to the user. Does anybody have C# code snippets or pointers to examples that do this basic error reporting/logging? Edit: At the time I asked this question I was really new to .NET and was unaware of System.Diagnostics.Trace. System.Diagnostics.Trace was what I needed at that time. Since then I have used log4net on projects where the logging requirements were larger and more complex. Just edit that 500 line XML configuration file and log4net will do everything you will ever need :)

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• php error reporting - having trouble matching local & web server settings

  - by Andrew Heath

  I'm trying to add a custom error handler to my site, but in doing so have discovered that my webhost's PHP error reporting settings and those of my localhost (default XAMPP) vary considerably. While I thought I was programming to E_STRICT like a good little boy, adding the error handler to my webhost revealed craploads of Runtime Notices. Example: Runtime notice strtotime() [function.strtotime]: It is not safe to rely on the system's timezone settings. Please use the date.timezone setting, the TZ environment variable or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Chicago' for 'CST/-6.0/no DST' instead In /home/... Clearly this isn't a red-alert, showstopping error. But what bothers me is that it doesn't show up on my localhost. I'd certainly like to improve my code by addressing these sorts of issues if I could see them! I've looked through both php.ini files, and my webhost's setting is error_reporting = E_ALL & ~E_NOTICE whereas mine was error_reporting = E_STRICT, which I had thought was better. However, changing mine to match and rebooting the server doesn't seem to have accomplished anything. Could someone please point me in the right direction?

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• Error handling approach on PHP

  - by Industrial

  Hi everybody, We have a web server that we're about to launch a number of applications onto. They will all share database and memcached servers, but each application has it's own mySQL database and all memcached keys per application, is prefixed. Possible scenario: If a memcached server in our cluster goes boom, we want someone (operative system admin) to be automatically contacted by email/iphone push notification or in any other appropriate way. If we we're about to install 150 identical applications for our customers on our servers, and a memcached server dies - all 150 applications will individually find this out and contact our system admin, which most certainly is going to think about getting a new job where he or she isn't about to be woken up by getting 150 messages sent 4:15 in the morning. Possible solution: One idea is to set up an external server for error handling that gets a $_POST or cURL request sent, and handles storage of the error message depending on the seriousness of the actual error message. It would of course check upon receiving the error call, that if the same memcached server have already been reported as offline, there would be no need to spam the system admin with additional reminders... The questions: What's a good approach on how to handle errors? How does the big guys in the industry handle this? Thanks!

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• Error monitoring/handling on webservers

  - by Industrial

  Hi everybody, We have a web server that we're about to launch a number of applications onto. They will all share database and memcached servers, but each application has it's own mySQL database and all memcached keys per application, is prefixed. Possible scenario: If a memcached server in our cluster goes boom, we want someone (operative system admin) to be automatically contacted by email/iphone push notification or in any other appropriate way. If we we're about to install 150 identical applications for our customers on our servers, and a memcached server dies - all 150 applications will individually find this out and contact our system admin, which most certainly is going to think about getting a new job where he or she isn't about to be woken up by getting 150 messages sent 4:15 in the morning. Possible solution: One idea is to set up an external server for error handling that gets a $_POST or cURL request sent, and handles storage of the error message depending on the seriousness of the actual error message. It would of course check upon receiving the error call, that if the same memcached server have already been reported as offline, there would be no need to spam the system admin with additional reminders... The questions: What's a good approach on how to handle errors? How does the big guys in the industry handle this? Thanks!

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• SQL SERVER – Puzzle – Challenge – Error While Converting Money to Decimal

  - by pinaldave

  Earlier I wrote SQL SERVER – Challenge – Puzzle – Usage of FAST Hint and I did receive some good comments. Here is another question to tease your mind. Run following script and you will see that it will thrown an error. DECLARE @mymoney MONEY; SET @mymoney = 12345.67; SELECT CAST(@mymoney AS DECIMAL(5,2)) MoneyInt; GO The datatype of money is also visually look similar to the decimal, why it would throw following error: Msg 8115, Level 16, State 8, Line 3 Arithmetic overflow error converting money to data type numeric. Please leave a comment with explanation and I will post a your answer on this blog with due credit. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Error Messages, SQL Puzzle, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology

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• Error caused by Dropbox in update manager

  - by Olivier Lalonde

  I am getting the following error message when the update manager runs: Apt Authentication issue Problem during package list update. The package list update failed with a authentication failure. This usually happens behind a network proxy server. Please try to click on the "Run this action now" button to correct the problem or update the list manually by running Update Manager and clicking on "Check". W: A error occurred during the signature verification. The repository is not updated and the previous index files will be used.GPG error: http://linux.dropbox.com lucid Release: The following signatures were invalid: NODATA 1 NODATA 2 W: Failed to fetch http://linux.dropbox.com/ubuntu/dists/lucid/Release W: Some index files failed to download, they have been ignored, or old ones used instead. This error started to appear recently and for no obvious reason (maybe because I created myself a private PGP key?). I'm running Dropbox v0.7.11 on Ubuntu Lucid 10.04.

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• Wammu, Samsung J700 error GetNextMemory code: 56

  - by Tamas

  I have got a (old) Samsung J700i. When connecting with a USB cabel to Wammu first the access was denied. Now it is oké... However, when I try to get info out from the phone... I get error message: Error whlie communicating with phone Desciption: Internal phone error. Function: GetNextMemory Error code: 56 I am using Ubuntu 12.04 and Wammu 0.36 Running on Python 2.7.3 Using wxPython 2.8.12.1 Using python-gammu 1.31.0 and Gammu 1.31.0 How may I access data on the phone? Thanks, Tamas

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• What layer to introduce human readable error messages?

  - by MrLane

  One of the things that I have never been happy with on any project I have worked on over the years and have really not been able to resolve myself is exactly at what tier in an application should human readable error information be retrieved for display to a user. A common approach that has worked well has been to return strongly typed/concrete "result objects" from the methods on the public surface of the business tier/API. A method on the interface may be: public ClearUserAccountsResult ClearUserAccounts(ClearUserAccountsParam param); And the result class implementation: public class ClearUserAccountsResult : IResult { public readonly List<Account> ClearedAccounts{get; set;} public readonly bool Success {get; set;} // Implements IResult public readonly string Message{get; set;} // Implements IResult, human readable // Constructor implemented here to set readonly properties... } This works great when the API needs to be exposed over WCF as the result object can be serialized. Again this is only done on the public surface of the API/business tier. The error message can also be looked up from the database, which means it can be changed and localized. However, it has always been suspect to me, this idea of returning human readable information from the business tier like this, partly because what constitutes the public surface of the API may change over time...and it may be the case that the API will need to be reused by other API components in the future that do not need the human readable string messages (and looking them up from a database would be an expensive waste). I am thinking a better approach is to keep the business objects free from such result objects and keep them simple and then retrieve human readable error strings somewhere closer to the UI layer or only in the UI itself, but I have two problems here: 1) The UI may be a remote client (Winforms/WPF/Silverlight) or an ASP.NET web application hosted on another server. In these cases the UI will have to fetch the error strings from the server. 2) Often there are multiple legitimate modes of failure. If the business tier becomes so vague and generic in the way it returns errors there may not be enough information exposed publicly to tell what the error actually was: i.e: if a method has 3 modes of legitimate failure but returns a boolean to indicate failure, you cannot work out what the appropriate message to display to the user should be. I have thought about using failure enums as a substitute, they can indicate a specific error that can be tested for and coded against. This is sometimes useful within the business tier itself as a way of passing via method returns the specifics of a failure rather than just a boolean, but it is not so good for serialization scenarios. Is there a well worn pattern for this? What do people think? Thanks.

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• Is goto to improve DRY-ness OK?

  - by Marco Scannadinari

  My code has many checks to detect errors in various cases (many conditions would result in the same error), inside a function returning an error struct. Instead of looking like this: err_struct myfunc(...) { err_struct error = { .error = false }; ... if(something) { error.error = true; error.description = "invalid input"; return error; } ... case 1024: error.error = true; error.description = "invalid input"; // same error, but different detection scenario return error; break; // don't comment on this break please (EDIT: pun unintended) ... Is use of goto in the following context considered better than the previous example? err_struct myfunc(...) { err_struct error = { .error = false }; ... if(something) goto invalid_input; ... case 1024: goto invalid_input; break; return error; invalid_input: error.error = true; error.description = "invalid input"; return error;

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• Runtime Error 424 Object Required

  - by Luis

  Hey so I get this error in this code: Private Sub Request_Stuff_button_Click() Call Main.createObjects Call My_Control.requestStuff End Sub at the 'Call My_Control.requestStuff' line. The 'Main' module looks like this: Public My_Control As ControlObject Public Sub createObjects() If My_Control Is Nothing Then Set My_Control = New ControlObject End If End Sub The weirdest thing is that when I add Dim x As Integer x = My_Control.dummyInt right before the line that gets me the error, x gets the correct value right before the error happens which means My_Control is definitely an object and is definitely not nothing. This error is killing me, thanks in advance.

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• weather-indicator: networking error: HTTP Error 403: Forbidden?

  - by quanta

  Here're the ~/.cache/indicator-weather.log: [Fetcher] 2012-11-24 11:45:52,619 - DEBUG - Indicator: getWeather for location 'Hanoi, Ha N?i, Vietnam' [Fetcher] 2012-11-24 11:45:52,620 - DEBUG - Indicator: getWeather: updating weather report [Fetcher] 2012-11-24 11:45:52,620 - DEBUG - Location: default weather source 'Google' chosen for 'Hanoi' [Fetcher] 2012-11-24 11:45:53,019 - ERROR - Indicator: networking error: HTTP Error 403: Forbidden [Fetcher] 2012-11-24 11:45:53,020 - DEBUG - Indicator: updateWeather: waiting for 'Cacher' thread to terminate [Fetcher] 2012-11-24 11:45:53,020 - ERROR - Indicator: updateWeather: could not get weather, leaving cached data

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• Setting useLegacyV2RuntimeActivationPolicy At Runtime

  - by Reed

  Version 4.0 of the .NET Framework included a new CLR which is almost entirely backwards compatible with the 2.0 version of the CLR.  However, by default, mixed-mode assemblies targeting .NET 3.5sp1 and earlier will fail to load in a .NET 4 application.  Fixing this requires setting useLegacyV2RuntimeActivationPolicy in your app.Config for the application.  While there are many good reasons for this decision, there are times when this is extremely frustrating, especially when writing a library.  As such, there are (rare) times when it would be beneficial to set this in code, at runtime, as well as verify that it’s running correctly prior to receiving a FileLoadException. Typically, loading a pre-.NET 4 mixed mode assembly is handled simply by changing your app.Config file, and including the relevant attribute in the startup element: <?xml version="1.0" encoding="utf-8" ?> <configuration> <startup useLegacyV2RuntimeActivationPolicy="true"> <supportedRuntime version="v4.0"/> </startup> </configuration> .csharpcode { background-color: #ffffff; font-family: consolas, "Courier New", courier, monospace; color: black; font-size: small } .csharpcode pre { background-color: #ffffff; font-family: consolas, "Courier New", courier, monospace; color: black; font-size: small } .csharpcode pre { margin: 0em } .csharpcode .rem { color: #008000 } .csharpcode .kwrd { color: #0000ff } .csharpcode .str { color: #006080 } .csharpcode .op { color: #0000c0 } .csharpcode .preproc { color: #cc6633 } .csharpcode .asp { background-color: #ffff00 } .csharpcode .html { color: #800000 } .csharpcode .attr { color: #ff0000 } .csharpcode .alt { background-color: #f4f4f4; margin: 0em; width: 100% } .csharpcode .lnum { color: #606060 } This causes your application to run correctly, and load the older, mixed-mode assembly without issues. For full details on what’s happening here and why, I recommend reading Mark Miller’s detailed explanation of this attribute and the reasoning behind it. Before I show any code, let me say: I strongly recommend using the official approach of using app.config to set this policy. That being said, there are (rare) times when, for one reason or another, changing the application configuration file is less than ideal. While this is the supported approach to handling this issue, the CLR Hosting API includes a means of setting this programmatically via the ICLRRuntimeInfo interface.  Normally, this is used if you’re hosting the CLR in a native application in order to set this, at runtime, prior to loading the assemblies.  However, the F# Samples include a nice trick showing how to load this API and bind this policy, at runtime.  This was required in order to host the Managed DirectX API, which is built against an older version of the CLR. This is fairly easy to port to C#.  Instead of a direct port, I also added a little addition – by trapping the COM exception received if unable to bind (which will occur if the 2.0 CLR is already bound), I also allow a runtime check of whether this property was setup properly: public static class RuntimePolicyHelper { public static bool LegacyV2RuntimeEnabledSuccessfully { get; private set; } static RuntimePolicyHelper() { ICLRRuntimeInfo clrRuntimeInfo = (ICLRRuntimeInfo)RuntimeEnvironment.GetRuntimeInterfaceAsObject( Guid.Empty, typeof(ICLRRuntimeInfo).GUID); try { clrRuntimeInfo.BindAsLegacyV2Runtime(); LegacyV2RuntimeEnabledSuccessfully = true; } catch (COMException) { // This occurs with an HRESULT meaning // "A different runtime was already bound to the legacy CLR version 2 activation policy." LegacyV2RuntimeEnabledSuccessfully = false; } } [ComImport] [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)] [Guid("BD39D1D2-BA2F-486A-89B0-B4B0CB466891")] private interface ICLRRuntimeInfo { void xGetVersionString(); void xGetRuntimeDirectory(); void xIsLoaded(); void xIsLoadable(); void xLoadErrorString(); void xLoadLibrary(); void xGetProcAddress(); void xGetInterface(); void xSetDefaultStartupFlags(); void xGetDefaultStartupFlags(); [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)] void BindAsLegacyV2Runtime(); } } Using this, it’s possible to not only set this at runtime, but also verify, prior to loading your mixed mode assembly, whether this will succeed. In my case, this was quite useful – I am working on a library purely for internal use which uses a numerical package that is supplied with both a completely managed as well as a native solver.  The native solver uses a CLR 2 mixed-mode assembly, but is dramatically faster than the pure managed approach.  By checking RuntimePolicyHelper.LegacyV2RuntimeEnabledSuccessfully at runtime, I can decide whether to enable the native solver, and only do so if I successfully bound this policy. There are some tricks required here – To enable this sort of fallback behavior, you must make these checks in a type that doesn’t cause the mixed mode assembly to be loaded.  In my case, this forced me to encapsulate the library I was using entirely in a separate class, perform the check, then pass through the required calls to that class.  Otherwise, the library will load before the hosting process gets enabled, which in turn will fail. This code will also, of course, try to enable the runtime policy before the first time you use this class – which typically means just before the first time you check the boolean value.  As a result, checking this early on in the application is more likely to allow it to work. Finally, if you’re using a library, this has to be called prior to the 2.0 CLR loading.  This will cause it to fail if you try to use it to enable this policy in a plugin for most third party applications that don’t have their app.config setup properly, as they will likely have already loaded the 2.0 runtime. As an example, take a simple audio player.  The code below shows how this can be used to properly, at runtime, only use the “native” API if this will succeed, and fallback (or raise a nicer exception) if this will fail: public class AudioPlayer { private IAudioEngine audioEngine; public AudioPlayer() { if (RuntimePolicyHelper.LegacyV2RuntimeEnabledSuccessfully) { // This will load a CLR 2 mixed mode assembly this.audioEngine = new AudioEngineNative(); } else { this.audioEngine = new AudioEngineManaged(); } } public void Play(string filename) { this.audioEngine.Play(filename); } } Now – the warning: This approach works, but I would be very hesitant to use it in public facing production code, especially for anything other than initializing your own application.  While this should work in a library, using it has a very nasty side effect: you change the runtime policy of the executing application in a way that is very hidden and non-obvious.

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