Piping output from one command into another command

[serbanrobu]

It's there a way of piping the output of a command into another? I'm trying to make this example working. But the stdin method expect a type T: Into<std::process::Stdio> as parameter. The following example would work if I used std::process::Command.

let child = tokio::process::Command::new("ls")
    .stdout(std::process::Stdio::piped())
    .spawn()?;
tokio::process::Command::new("grep")
    .arg("a")
    .stdin(child.stdout.unwrap())
    .spawn()?;

I get the following error:

the trait bound `Stdio: From<tokio::process::ChildStdout>` is not satisfied [...]

[ipetkov]

Hi @serbanrobu, thanks for bringing this up! As things stand today there isn't an ergonomic way to perform the conversion, but I've opened #3466 which should make this easier to perform the conversion.

In the meantime, you could try getting yourself unblocked by manually creating an anonymous pipe and passing in the write/read ends into the child processes (tokio will not capture and manage the child's stdio handles if they are explicitly set to a particular file descriptor).

Hope this helps, but don't hesitate to ask if you have other questions!

[serbanrobu]

Thank you!