Hello, I'm trying to use a native lib with `jvmArg...

# compose-desktop

[Josenaldo]

Hello, I'm trying to use a native lib with jvmArgs += "-Djava.library.path=%PATH%;C:\path\to\mylib" in Windows, but when I load it with System.loadLibrary(libname) , I get an UnsatisfiedLinkError. I'm trying to build an executable file with the createDistributable gradle task from this Compose Multiplatform tutorial.

What I don't understand is why System.getProperty("java.library.path") results in %PATH%;C:pathtomylib , without backslashes and without %PATH% being actually resolved. I want the property to be the content of PATH together with the path to my lib, i.e. something like C:\path\one;C:\path\two;C:\path\to\mylib.

I found out that surrounding the final path with quotes ("-Djava.library.path="\"%PATH%;C:\path\to\mylib\"") brings back backslashes, but the issue with %PATH% persists. The next attempt was "-Djava.library.path="\"${System.getenv("PATH")};C:\path\to\mylib\"" , but then the createDistributable task itself threw a TaskExecutionException, with the error log being Error: Invalid Option: [Files\Git\cmd;C:\Users\tempj\AppData\Local\Microsoft\WindowsApps;;C:\path\to\mylib'] (I suspect that the single quote at the end might be the culprit, but I myself didn't insert it...).

[Josenaldo]

Also, the whole thing works when I simply modify the PATH variable to include C:\path\to\mylib, so that's why I'm attempting to set the library path to PATH + the path to the lib.

[ephemient]

double up the backslashes, they're being treated as escapes

[Michael Paus]

It is not a good idea from the very beginning to use such a platform-specific and absolute path. Instead you should follow these instruction to adding-files-to-packaged-application and then set the following property very early in your desktop specific code.

System.getProperty("compose.application.resources.dir")?.let { System.setProperty("java.library.path", "${System.getProperty("java.library.path")}${File.pathSeparator}${it}") }

In your case the library should be placed in

desktopApp/resources/windows-x64/yourlibrary.dll