Child process hangs waiting for EOF (end fo file) when using stdin(Command.PIPED)

[ValdezFOmar]

What system are you running Yazi on?

Linux X11

What terminal are you running Yazi in?

kitty 0.35.2

yazi --debug output

Yazi
    Version: 0.3.0 (36381e6 2024-08-10)
    Debug  : false
    OS     : linux-x86_64 (unix)

Ya
    Version: 0.3.0

Emulator
    Emulator.via_env: ("xterm-kitty", "")
    Emulator.via_csi: Ok(Kitty)
    Emulator.detect : Kitty

Adapter
    Adapter.matches: Kitty

Desktop
    XDG_SESSION_TYPE: Some("x11")
    WAYLAND_DISPLAY : None
    DISPLAY         : Some(":0")

SSH
    shared.in_ssh_connection: false

WSL
    /proc/sys/fs/binfmt_misc/WSLInterop: false

Variables
    SHELL              : Some("/usr/bin/bash")
    EDITOR             : Some("nvim")
    YAZI_FILE_ONE      : None
    YAZI_CONFIG_HOME   : None
    ZELLIJ_SESSION_NAME: None

Text Opener
    default: Some(Opener { run: "${EDITOR:-vi} \"$@\"", block: true, orphan: false, desc: "$EDITOR", for_: None, spread: true })
    block  : Some(Opener { run: "${EDITOR:-vi} \"$@\"", block: true, orphan: false, desc: "$EDITOR", for_: None, spread: true })

tmux
    TMUX   : false
    Version: No such file or directory (os error 2)

Dependencies
    file             : 5.45
    ueberzugpp       : No such file or directory (os error 2)
    ffmpegthumbnailer: No such file or directory (os error 2)
    magick           : No such file or directory (os error 2)
    fzf              : 0.54.3
    fd               : 10.1.0
    rg               : 14.1.0
    chafa            : No such file or directory (os error 2)
    zoxide           : No such file or directory (os error 2)
    7z               : 17.05
    7zz              : No such file or directory (os error 2)
    jq               : No such file or directory (os error 2)


--------------------------------------------------

Did you try the latest nightly build to see if the problem got fixed?

Yes, and I updated the debug information above (yazi --debug) to the nightly that I tried

Describe the bug

When setting the stdin of a child process to be piped and spawning it (e.g. Command('rev'):stdin(Command.PIPED):spawn()) I can write to its input, but then process never completes. The task manager shows that the process is still open, it just has not exit and there's no error (even on the logs):

Minimal reproducer

Plugin at ~/.config/yazi/plugins/repro.yazi/init.lua

local function async_entry()
    local child = assert(Command('rev'):stdin(Command.PIPED):spawn())
    child:write_all('Hello world!\n')
    child:flush()
    local out = assert(child:wait_with_output())
    -- The process keeps wating for EOF and this line isn't reached
    ya.err(out.stdout)
end

return { entry = async_entry }

Keymap:

[[manager.append_keymap]]
on = '<C-l>'
run = 'plugin repro'

Anything else?

The example from the documentation works as expected, so I suspected that maybe what is causing the problem is that stdin is not being closed, thus the process doesn't reach the EOF and it just hangs there waiting for more data. The example from the docs works because as soon as echo exits, its stdout stream is closed and the piped stdin of rev reaches the EOF.

I try searching in the docs if there's a Child:close() method to manually close stdin but it seems that this functionality doesn't exists (even though there's write_all and flush methods). Maybe provide a close() method to close stdin so the child process can reach the EOF?

[sxyazi]

Nice catch! Should be fixed in #1464

BTW you need to specify the stdout(Command.PIPED) if you want to retrieve back the stdout:

- local child = assert(Command('rev'):stdin(Command.PIPED):spawn())
+ local child = assert(Command('rev'):stdin(Command.PIPED):stdout(Command.PIPED):spawn())

[ValdezFOmar]

It works now, thanks!
And yes, I was to focus with the stdin that I forgot about piping stdout, thanks for the remainder.

[github-actions]

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