how may I execute a native command and retrieve its output? <This> returns an empty string instead o...

# kotlin-native

[elect]

how may I execute a native command and retrieve its output? This returns an empty string instead of

elect@5800x:~/IdeaProjects/java-launcher$ echo $JAVA_HOME
/usr/lib/jvm/java-11-openjdk-amd64

[Adam S]

I'd guess JAVA_HOME isn't set in the context of the native program. What happens if you try echo blah instead?

[elect]

but on a terminal is..
could be the kotlin native environment is different?

[Adam S]

it could be

[elect]

indeed, you are right

[elect]

"echo JAVA_HOME" -> JAVA_HOME

[elect]

uhm, this is disappointing

[elect]

I can see that

printenv

isn't empty (list of all envs), but JAVA_HOME isn't there unfortunately..

[Adam S]

environment variables are a black magic to me, I know it's really hard to set a global env var on macOS, but if you're using Linux or Windows it should be easier

[Adam S]

alternatively you can use Gradle and try to pass in an environment variable

import org.jetbrains.kotlin.gradle.plugin.mpp.Executable
import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinNativeTarget

kotlin {
  targets.withType<KotlinNativeTarget>().configureEach {
    binaries.withType<Executable>().configureEach {
      runTaskProvider?.configure {
        environment("JAVA_HOME", System.getProperty("java.home"))
      }
    }
  }
}

(not tested, but I've used something similar before)

[elect]

null

[elect]

just to be sure, Executable is from org.jetbrain.kotlin.gradle.plugin.mpp?

[Adam S]

yes (I added the imports above)

[Adam S]

maybe JAVA_HOME is null in your build script too 🙃

[Adam S]

if you run the Gradle command from your shell it should pass the JAVA_HOME value through...

[Adam S]

oh, duh, try System.getProperty("java.home")

https://stackoverflow.com/questions/16297326/checking-getting-java-home-variable-from-java

[elect]

uhm, better

/home/elect/.jdks/openjdk-19.0.1

[elect]

but still not the above

[elect]

fine

[Adam S]

I guess you're running with IntelliJ, and it's configured to use jdk19

[elect]

yep

[elect]

I'm using the gui, running the gradle runDebugExecutableNative

[elect]

you know what, from running via ./gradlew rDEN it works flawless, JAVA_HOME is properly read.. the issue rises up only via Idea gui..

[Adam S]

what OS are you using?

[elect]

Ubuntu

[Adam S]

have you tried using jenv or setting a global environment variable? https://askubuntu.com/questions/261760/setting-global-environment-variable-for-everyone

[elect]

no, not yet
but I'm fine having it working from CLI