Changing process.title does nothing

[brownjoel]

What version of Bun is running?

1.1.29+6d43b3662

What platform is your computer?

Darwin 23.5.0 x86_64 i386 and Linux 6.8.0-40-generic x86_64 x86_64

What steps can reproduce the bug?

Run

bun -e "process.title='foo'; console.log(process.title)"

What is the expected behavior?

foo to be printed to the console.

What do you see instead?

bun is printed to the console.

Additional information

If run with node 20, this works as expected:

% node -e "process.title='foo'; console.log(process.title)"
% foo

Welcome to Node.js v20.11.0.
Type ".help" for more information.
> process.title='foo'
'foo'
> console.log(process.title)
foo

In bun:

Welcome to Bun v1.1.29
Type ".help" for more information.
[!] Please note that the REPL implementation is still experimental!
    Don't consider it to be representative of the stability or behavior of Bun overall.
> process.title='foo'
'foo'
> console.log(process.title)
bun

Tested on a variety of machines, including macOS and Ubuntu.

[dylan-conway]

This is a bug in src/bun.js/bindings/exports.zig. Process.setTitle/getTitle should be saving input titles.

[CarlosEduR]

@dylan-conway nice, thanks for adding the labels! as this is a good first issue, I wanna take a look!

[brownjoel]

Related (and I'm sorry this wasn't clear enough in the original ticket):
Will a fix to this affect the actual process' title, as it does in node? I'm less concerned that the field process.title is retained and more that this field is a mechanism for creating clear and known process titles for which other processes can interact.
e.g. copied from the Node docs:

Assigning a new value to process.title modifies the current value of ps.

[RiskyMH]

I find it interesting how this works on windows but not linux (normally its the other way around).

[RiskyMH]

This appears to work now! Probably from #16026 by @nektro.

Edit: seems to be only the variable change, not actually changing the title.

[Jarred-Sumner]

This isn’t implemented yet on posix

[nektro]

❯ bun-debug --version
1.1.42-debug

❯ bun-debug -e "process.title='foo'; console.log(process.title)"
foo

❯ uname -a
Darwin Mac 24.1.0 Darwin Kernel Version 24.1.0: Thu Oct 10 21:05:23 PDT 2024; root:xnu-11215.41.3~2/RELEASE_ARM64_T6031 arm64

[Jarred-Sumner]

@nektro the purpose of process.title is not to add a getter/setter called process.title

the purpose of process.title is to impact how it appears in Activity Monitor, in top, in htop, and to other applications

We cannot mark this issue as fixed until process.title does what it was designed to do