panicked at 'the runtime has not been set'

[iMiamas]

when i run application to this：
let stream = TcpStream::connect(server).await?;

rootthread ':' panicked at 'the runtime has not been set '

i use rust as a lib， does not have main func ，so i can not use "#[runtime:main]",or i don't kown how to use "#[runtime:main]"

[iMiamas]

i want to kown how can i solve this problem？

[yoshuawuyts]

When you say: "I use Rust as a lib" does that mean you're then calling it from C/C++? There's been conversations about writing a non-attribute version of the entry macros (likely block_on, see in part #73) which may help with this.

But currently it's not possible quite yet; apologies!

[iMiamas]

yes，i calling api（writted by rust） from c，and in my rust api progrem， i use runtime packge
and the problem as above。thank you so much！

[stbuehler]

I have a similar problem with clap: as the clap::App isn't Send I had to split the main function into a sync (clap) and an async part. Given I need a nightly compiler anyway (i.e. it might break anytime) I didn't mind using the hidden runtime::raw::enter like this:

// sync part of main
runtime::raw::enter(runtime_tokio::TokioCurrentThread, async move {
    // async part of main
});