Open
Description
Version
│ │ ├── tokio v1.43.0
│ │ │ └── tokio-macros v2.5.0 (proc-macro)
│ │ └── tokio-util v0.7.13
│ │ └── tokio v1.43.0 (*)
│ ├── tokio v1.43.0 (*)
│ ├── tokio-rustls v0.24.1
│ │ └── tokio v1.43.0 (*)
│ ├── tokio-stream v0.1.17
│ │ └── tokio v1.43.0 (*)
│ ├── tokio-util v0.7.13 (*)
│ │ ├── tokio v1.43.0 (*)
│ │ │ ├── tokio v1.43.0 (*)
│ │ ├── tokio v1.43.0 (*)
│ │ ├── tokio-rustls v0.26.1
│ │ │ └── tokio v1.43.0 (*)
│ ├── tokio v1.43.0 (*)
│ ├── tokio-rustls v0.26.1 (*)
│ ├── tokio-socks v0.5.2
│ │ └── tokio v1.43.0 (*)
│ ├── tokio-util v0.7.13 (*)
│ │ ├── tokio v1.43.0 (*)
├── tokio v1.43.0 (*)
├── tokio-socks v0.5.2 (*)
Platform
Linux redacted 6.7.6-hardened1-1-hardened #1 SMP PREEMPT_DYNAMIC Sat, 24 Feb 2024 23:47:28 +0000 x86_64 GNU/Linux
Description
I had code along the lines of:
let value: Cow<'_, [u8]> = /* some stuff here */;
stdout.write_all(&value).await?;The program exits almost immediately afterwards. Upon testing I noticed it would sometimes fail to print anything, I first assumed a bug in my implementation but adding stdout.flush().await?; made the problem go away, and ##rust on irc confirmed stdout is buffered in Rust:
let value: Cow<'_, [u8]> = /* some stuff here */;
stdout.write_all(&value).await?;
stdout.flush().await?;Usually the Rust standard library flushes stdout on exit:
12:41 <Alexendoo> kpcyrd: The unwritten output is flushed at a normal exit though (return from main/std::process::exit)
It seems this doesn't work well with tokio, possibly because it would require an .await, although #[tokio::main] should be able to do this for me, so I don't have to sprinkle stdout.flush().await?; throughout my codebase to avoid silent data loss.