Heyo! I'm looking to write a simple app log file u...

# squarelibraries

[Drake Gebhart]

Heyo! I'm looking to write a simple app log file using Okio on Kotlin Multiplatform for iOS/Android. This will literally just be a text file and I'm just writing strings to it.

I added Okio to my KMP project and in my commonMain I wrote the example provided:

val path = "applog.txt".toPath()       
        FileSystem.SYSTEM.appendingSink(path).buffer().use { sink ->
            sink.writeUtf8(message)
        }

I get an error on both iOS and Android

Caused by: java.io.FileNotFoundException: applog.txt: open failed: EROFS (Read-only file system)
	at libcore.io.IoBridge.open(IoBridge.java:492)
	at java.io.FileOutputStream.<init>(FileOutputStream.java:236)
	at okio.Okio__JvmOkioKt.sink(JvmOkio.kt:173)

Looking around it looks like Okio w/ KMP works in common now but I'm not seeing many examples?

[jw]

Your path is relative, and the working directory is probably something unusable like /.

[jw]

Where are you expecting the file to go?

[Drake Gebhart]

Just in the app container, so for android /data/data/com.appname/

[jw]

That is the path you should specify then, although ideally deriving it from the getDataDir API or whatever it's called

[Drake Gebhart]

getDataDir from okio or just using expect/actuals with iOS/Android? Not seeing anything in okio api so likely just gonna do the expect/actuals

[jw]

I don't know what your code looks like, but you could also just inject the base Path into your common code as a parameter and then build upon that with relative paths.

[Drake Gebhart]

Yeah sounds good, thanks!