Non-C locale detected. This is not supported. Call 'setlocale(LC_NUMERIC, "C");' in your code.

[brys0]

Non-C locale detected. This is not supported.
Call 'setlocale(LC_NUMERIC, "C");' in your code.
SIGSEGV: segmentation violation
PC=0x7549acc97ef4 m=9 sigcode=1 addr=0x98
signal arrived during cgo execution

goroutine 7 gp=0xc0000b2380 m=9 mp=0xc00006e308 [syscall]:
runtime.cgocall(0xbe7ef0, 0xc000078928)
/usr/lib/go-1.23/src/runtime/cgocall.go:167 +0x4b fp=0xc0000788e8 sp=0xc0000788b0 pc=0x47becb
github.com/gen2brain/go-mpv._Cfunc_mpv_request_log_messages(0x0, 0x29d50ec0)
_cgo_gotypes.go:378 +0x4b fp=0xc000078928 sp=0xc0000788e8 pc=0x5a1b4b
github.com/gen2brain/go-mpv.(*Mpv).RequestLogMessages.func2(0xc00011eca0, 0x29d50ec0)
/home/brys0/go/pkg/mod/github.com/gen2brain/go-mpv@v0.2.3/client.go:271 +0x6f fp=0xc000078978 sp=0xc000078928 pc=0x5a4e8f

[gen2brain]

Use something like this:

const LcNumeric = int(C.LC_NUMERIC)

func setLocale(lc int, locale string) {
        l := C.CString(locale)
        defer C.free(unsafe.Pointer(l))
        C.setlocale(C.int(lc), l)
}

And then in your main, before anything call setLocale(LcNumeric, "C").

[gen2brain]

You are probably using Qt, GTK, or something that sets and changes locale, and libmpv doesn't like that, the message to Call 'setlocale(LC_NUMERIC, "C");' in your code. comes from libmpv.

[brys0]

Unfortunately the error is still occurring, and you are right about that. I am trying to build a wails app, which on linux builds with gtk3. I tried using the purego implementation but when trying to "loadfile" in a bound method returns an unknown error, otherwise it works fine.

You can see my demo here: https://github.com/brys0/wails-mpv-example

[gen2brain]

Well, just see if you are calling at the right time, try to set it after GTK is initialized then. Anyway, this is not an issue for this repo and nothing I can do. Not sure what you mean by bound method.

[brys0]

Wails has the ability to bind methods from the backend (go code) to frontend (js/window) when trying to call that method from JS I receive the random error, but elsewhere it still works correctly.

[brys0]

Yes, I know, I'm sorry its not related but I really appreciate the help.

[brys0]

At least on windows the purego implementation when running "loadfile" command makes an unknown error. I can't get the Cgo version working, I tried installing vcpkg, to install pkgconf but the import still doesn't work.

[gen2brain]

How are those methods called, you usually don't want to start windows and OpenGL from some goroutine, it must be from the main thread. But that unknown error can also be related to setLocale. Who returns that unknown error?

[brys0]

How are those methods called, you usually don't want to start windows and OpenGL from some goroutine, it must be from the main thread. But that unknown error can also be related to setLocale. Who returns that unknown error?

If you're talking about how the methods are called from the JS frontend the "IPC" is just a regular websocket wails is listening to for development mode, it looks for the right method call, then finds the method and calls it in a goroutine.

The weird thing is it works fine from a go routine, just never works when being called from the bound method.
Stack trace

panic: unknown error

goroutine 59 [running]:
main.startProcessMPV()
        L:/Projects/shadfin/wails-mpv-example/app.go:52 +0x11e5
main.(*App).StartMPV(0xc000200b20)
        L:/Projects/shadfin/wails-mpv-example/app.go:30 +0x14
reflect.Value.call({0x1241020, 0xc000200b20, 0x213}, {0x12d8409, 0x4}, {0x17d1220, 0x0, 0x0})
        C:/Program Files/Go/src/reflect/value.go:581 +0xea5
reflect.Value.Call({0x1241020, 0xc000200b20, 0x213}, {0x17d1220, 0x0, 0x0})
        C:/Program Files/Go/src/reflect/value.go:365 +0xb3
[github.com/wailsapp/wails/v2/internal/binding.(*BoundMethod).Call](http://github.com/wailsapp/wails/v2/internal/binding.(*BoundMethod).Call)(0xc000252310, {0x17d1220, 0x0, 0x0})
        C:/Users/bryso/go/pkg/mod/github.com/wailsapp/wails/v2@v2.9.2/internal/binding/boundMethod.go:72 +0x3ff
[github.com/wailsapp/wails/v2/internal/frontend/dispatcher.(*Dispatcher).processCallMessage](http://github.com/wailsapp/wails/v2/internal/frontend/dispatcher.(*Dispatcher).processCallMessage)(0xc000212c00, {0xc000030180, 0x53}, {0x1397250, 0xc000246100})
        C:/Users/bryso/go/pkg/mod/github.com/wailsapp/wails/v2@v2.9.2/internal/frontend/dispatcher/calls.go:45 +0x630
[github.com/wailsapp/wails/v2/internal/frontend/dispatcher.(*Dispatcher).ProcessMessage](http://github.com/wailsapp/wails/v2/internal/frontend/dispatcher.(*Dispatcher).ProcessMessage)(0xc000212c00, {0xc000030180, 0x53}, {0x1397250, 0xc000246100})
        C:/Users/bryso/go/pkg/mod/github.com/wailsapp/wails/v2@v2.9.2/internal/frontend/dispatcher/dispatcher.go:42 +0x22b
[github.com/wailsapp/wails/v2/internal/frontend/desktop/windows.(*Frontend).dispatchMessage](http://github.com/wailsapp/wails/v2/internal/frontend/desktop/windows.(*Frontend).dispatchMessage)(0xc000246100, {0xc000030180, 0x53})
        C:/Users/bryso/go/pkg/mod/github.com/wailsapp/wails/v2@v2.9.2/internal/frontend/desktop/windows/frontend.go:776 +0x7b
created by [github.com/wailsapp/wails/v2/internal/frontend/desktop/windows.(*Frontend).processMessage](http://github.com/wailsapp/wails/v2/internal/frontend/desktop/windows.(*Frontend).processMessage) in goroutine 1
        C:/Users/bryso/go/pkg/mod/github.com/wailsapp/wails/v2@v2.9.2/internal/frontend/desktop/windows/frontend.go:713 +0x82a

[gen2brain]

Yes, exactly what is wrong, it calls it in a goroutine. You can try to use runtime.LockOSThread in init().

[brys0]

Yes, exactly what is wrong, it calls it in a goroutine. You can try to use runtime.LockOSThread in init().

You mean the mpv initialize() ?

[gen2brain]

I mean opening window, opengl context, you cannot initialize such things in goroutine. X11 may be tolerant, Windows API is not, macOS API is not, etc.

[gen2brain]

I mean init(), not mpv.

[brys0]

Will the OS thread be locked for the full duration of the program?

[gen2brain]

Hopefully yes.