Where to store external DLL/DYLIB files

Getting Started
1

Hi,

I have problems understanding how to work with external dlls/dylibs file in my Xojo project.

I’m using soft declares to functions of an external dll/dylib file, both on Windows and Mac. On Mac my app can find and use the dylib file if I use the full path to the file, e.g. /Users/username/projects/xojoapp/mylib.dylib. On Windows it only works if I place the dll file into the C:\windws folder.

I can’t imagine that this is the recommended way to handle external libraries. What is the best/usual way to store (and later deploy) external libraries and use them during development (just click the Run button in Xojo) and build/deploy?

Thanks for any help.

2

right next to your executable on windows (Parent directory).
on mac place them inside the Frameworks folder (using a Post build CopyFileStep)

Then just call the libname.dylib or libname.dll depending on the platform.

3

Just use a copy file step to place the DLL next to your program executable or in the frameworks bundle folder.

4

Can you add the an application subfolder to the PATH variable?

System.EnvironmentVariable("PATH") = pathToSubfolder

I have to do this to get VLC and Quicktime (older versions) to work on windows.

5

The only way I see to achieve that would be to run a .Bat file containing the line you posted. Not shell to it. Point a folderItem to it and do a launch. That way it will be added to the system variables.

6

On Windows be aware that this will overwrite everything in the PATH variable, which might cause problems. It’s better to append/prepend (ordering is significant) your custom directory to the variable rather than overwrite:

Dim s As String = System.EnvironmentVariable("PATH") System.EnvironmentVariable("PATH") = s + ";" + pathToSubfolder //searched LAST // OR System.EnvironmentVariable("PATH") = pathToSubfolder + ";" + s //searched FIRST

7

[quote=367157:@Andrew Lambert]On Windows be aware that this will overwrite everything in the PATH variable, which might cause problems. It’s better to append/prepend (ordering is significant) your custom directory to the variable rather than overwrite:

Dim s As String = System.EnvironmentVariable("PATH") System.EnvironmentVariable("PATH") = s + ";" + pathToSubfolder //searched LAST // OR System.EnvironmentVariable("PATH") = pathToSubfolder + ";" + s //searched FIRST[/quote]

Good point, I had problems with PATH being too long to append to and I did not need to look in other locations so this was fine for me. Note this will only effect your running application.

8

On Mac the PATH wouldn’t work for libraries. There was a setting for a dylibs alternative paths in past, but was removed due to security concerns.

However on Mac you can use the @executable_path shortcut. See https://wincent.com/wiki/%40executable_path%2C_%40load_path_and_%40rpath for more info.