Problem with sync.WaitGroup and gtk?

[copiesofcopies]

I'm developing on Debian. I'm trying to use sync.WaitGroup in a program using the ui library, and it keeps dumping with this message:

[xcb] Unknown sequence number while processing queue
[xcb] Most likely this is a multi-threaded client and XInitThreads has not been called
[xcb] Aborting, sorry about that.

It could be that I just don't understand what I'm doing yet (quite likely). But I also found this: http://stackoverflow.com/questions/18647475/threading-problems-with-gtk

Call XInitThreads(). This should be done before gtk_init, that will stop the messages!

[copiesofcopies]

Until further notice, I'm assuming this is a race condition I've created and that I just don't understand concurrency.

[andlabs]

Can you provide some sample code? (I do need to write documentation...)

[copiesofcopies]

Sure, the code is here, and the problem is in main.go. main() starts listAccounts() as a goroutine, and when the user clicks the "Add" button to add a new account, listAccounts() starts editAccount(), passing it the address of an Account struct, then waits for it to finish changing the contents of the struct. My operating assumption is that I need to put a lock in here somewhere.

[copiesofcopies]

For what it's worth, the race detector didn't find a race here. Here is the full error message I'm getting at the moment.

[copiesofcopies]

I stripped the program down to its bare essentials: just a window with a button that starts a goroutine to open a second window. The program is still unstable, and crashes with X-related errors like this:

(ui-test:14391): Gdk-WARNING **: ui-test: Fatal IO error 11 (Resource temporarily unavailable) on X server :0.

Or like this longer error. Any idea what might be the problem?

[copiesofcopies]

And I figured out the problem: you can't open a second window in a goroutine. When I remove "go" from before the call to the function that opens the second window, the crashes disappear.

[andlabs]

Right, you'll need to do ui.Do() in that goroutine call as well.

I really wish I didn't need to use that hacky workaround, but my previous attempts at using channels for events caused lots of problems :(

[copiesofcopies]

Oh, I see -- ui.Do() is necessary anytime you call a goroutine that opens a window, not just in main()? I hadn't understood that from the documentation.

Simply dropping "go" and calling it as a normal function seems to be working perfectly well for me so far. Thanks for your replies -- if I can help with documentation, let me know!

[andlabs]

Right, because your code is technically still running in ui.Do() =P The docs need work, yes; I did write a getting started guide on the wiki.