Can the --entrypoint command take any arguments?

[christophberger]

Hi,

I try to run a command with a flag as an entrypoint (like mycommand --flag value). I didn't find a syntax that works. Is this possible at all?

[appcypher]

The commands and args come after the --

msb run <image> -- mycommand --flag value

Also:

msb run <image> --entrypoint mycommand -- --flag value

[christophberger]

For some reason, this does not work with create:

> msb create ubuntu --name test --entrypoint /usr/bin/env -- bash
error: unexpected argument 'bash' found

Usage: msb create [OPTIONS] <IMAGE>

For more information, try '--help'.

Counter test: msb run works fine:

2 > msb run ubuntu --name test --entrypoint /usr/bin/env -- bash
root@test:/#

[appcypher]

create's main function is to create and start the sandbox. it does not run a command at the same time.

if your goal is to create and run, then what you did after is correct:

msb run ubuntu --name test --entrypoint /usr/bin/env -- bash

msb run basically is a version of create that lets you run a command at the same time.
and when you specify a name like in --name test, the sandbox is persisted, so can keep accessing the same sandbox in the future.

[christophberger]

Got it, but when I set an entry point, I don't want to necessarily use it right away. Like with a Dockerfile, I would have expected that the entrypoint parameter sets the entry point for whenever the container (or VM, in case of Microsandbox) starts.

[appcypher]

Like with a Dockerfile, I would have expected that the entrypoint parameter sets the entry point for whenever the container (or VM, in case of Microsandbox) starts.

It actually works that way today.

msb create python --name py --entrypoint bash # you can specify entrypoint when you start a sandbox 

msb exec py -- -c "echo hello" # and you can specify arguments to the entrypoint when you exec

That's how Docker also handles entrypoint.

But I think I understand what you mean, you want arguments as well when you create the VM. You can use scripts for that.

msb create python --name py2 --script start='bash -c "echo hello"'

msb exec py2 -- start

You can even have multiple scripts.

We will also have Sandboxfile in the future that helps with this.

[cboct]

Thanks for clarifying! The script approach is fine with me.

[appcypher]

Just realized that --script arg don't quite work the way I would imagined.
Right now you need to do this ugly thing:

msb create python --name py2 --script start=$'#!/bin/sh\necho hello\n'

But i will fix that very soon so you don't have to specify the shebang.