同时启动多个实例时，VisionProxy.dll上出现Sikuli脚本IO错误

Question

I have the following problem on Windows. I am using SikuliScript in interactive mode which is working fine. That's the commandline I use to launch it:

"C:\Program Files (x86)\Java\jre6\bin\java.exe" -jar "E:\APPS\Sikuli\Runtime\sikuli-script.jar" -i

However if I launch this command at least twice roughly at the same time (either manually or via Scheduled Tasks) I'll get a Java Exception because VisionProxy.dll already exists in my Temp Directory and cannot be overwritten because it's actively in use (by the other command of course):

java.io.FileNotFoundException: C:\Users\%USERNAME%\AppData\Local\Temp\2\tmplib\VisionProxy.dll (The process cannot access the file because it is being used by another process)
at java.io.FileOutputStream.open(Native Method)
at java.io.FileOutputStream.<init>(Unknown Source)
at java.io.FileOutputStream.<init>(Unknown Source)

The DLL gets put there by Sikuli itself when the library gets loaded so I don't know how to prevent this. Has anyone had a similar problem and solved it?

Thanks & Regards

Answer 1

There's no quick and easy fix for this.

What's happening is that the sikuli-script jar is using a little trick to allow it to be packaged as a single self-contained jar. The jar file contains all the native libraries that it might need, and when you run it, the code figures out which one you actually need (Windows_x86, maybe), pulls it out of the jar into the temp directory, and then dynamically links it. Running two in a row as your doing makes the DLL extraction process fail because one process stomps on the others' files.

The only fix for this is changing the code. You'll need to get the source code for Sikuli, find where it's performing the dynamic link trick, and remove that. Then you'll need to build it yourself and manually link against the DLL. That will allow you to run multiple instances at once (although I'm not sure how useful that will be).