7 ms·

Does anyone know how different a Fuchsia program is from a Linux program? OS APIs, memory model, security model, etc.

by dlojudice 6y ago

CameronNemo 6y ago
If they do, they are likely a google engineer.
- lima 6y ago
  ... aaand a Google engineer showed up to answer the question. The beauty of HN :)
  - CameronNemo 6y ago
    It's all fun and games until I have to learn about Zircon to control the software running on hardware I "own".
- PoignardAzur 6y ago
  Not really, you can be a microkernel hobbyist or just curious. I've had some idea of how Zirkon (Fuschia's microkernel) worked for about a year now, and I'm very much in the above categories.
  - CameronNemo 6y ago
    You may be an atypical case. Are you working in anything microkernel related?
    - PoignardAzur 6y ago
      No.
tyingq 6y ago
This covers some of that. https://fuchsia.googlesource.com/docs/+/refs/heads/sandbox/jschein/default/libc.md https://fuchsia.googlesource.com/docs/+/refs/heads/sandbox/j...
linuxftw 6y ago
Fuchsia's not a real thing and it's never going to be. You don't have to worry about it, it's just a make-work project for some people at google to feel cool.
- dane-pgp 6y ago
  More likely, Google have done threat modelling of their entire business and worked out that if there was ever some legal problem with using Linux (like the infamous SCO case), the amount of economic damage it would do to them would be more than whatever resources they are spending on coming up with an alternative (which will hopefully never need to be used). Also, just as Chrome gave them a seat at the table of web standardisation, and a chance to try new ideas that didn't have to go through Mozilla's approval process, having a kernel of their own allows them to influence the OS design space in ways that are more aligned to their business goals, and without needing Linus's approval.
  - linuxftw 6y ago
    They can use BSD to build whatever they want if they're worried about the GPL. I think that someone at google built fuschia for the sake of building it. Their core business is still search, that's all Android is. If they launch their own fuschia based handset, people are unlikely to switch, OEMs are unlikely to switch. It's just a failed concept.
    - cycloptic 6y ago
      See some of the sibling comments, fuchsia is BSD-licensed and has a new design not based on any Unix.
      - linuxftw 6y ago
        I'm talking about BSD the operating system concerning the OP's assertion of managing risk. Last I checked (years ago), the userspace was implemented partially with musl, which reads > 'musl, pronounced like the word "mussel", is an MIT-licensed implementation of the standard C library targetting the Linux syscall API, Now, they're announcing running Linux programs on Fuchsia. Sure seems to me they're implementing a Unix-like system, even if their kernel was written from scratch. The BSD world doesn't consider the userspace very separate from the kernel space, it's all part of a single system. I would argue it's very much 'based on Unix' as soon as they start adding POSIX APIs. They're adding POSIX APIs because they work.
abarth 6y ago
The memory model is similar (a flat, linear address space). The OS APIs are quite different. Fuchsia's OS APIs are designed around an object-capability discipline. For example, almost all the syscalls take a zx_handle_t as their first argument, which means they are operations on an object the process has previously been granted access explicitly. In Linux, many OS APIs operate on the "ambient" environment rather than on a specific kernel object. Disclosure: I work on Fuchsia.
saagarjha 6y ago
It's fairly different; the OS is built on capabilities and exposing its system API via libc. By default applications get nothing. Resources are objects. IPC is done using a wire format called FIDL.
- The_rationalist 6y ago
  What does FIDl bring over d-bus or say mojo ?

Does anyone know how different a Fuchsia program is from a Linux program? OS APIs, memory model, security model, etc.

CameronNemo 6y ago

If they do, they are likely a google engineer.

lima 6y ago
... aaand a Google engineer showed up to answer the question. The beauty of HN :)
- CameronNemo 6y ago
  It's all fun and games until I have to learn about Zircon to control the software running on hardware I "own".
PoignardAzur 6y ago
Not really, you can be a microkernel hobbyist or just curious. I've had some idea of how Zirkon (Fuschia's microkernel) worked for about a year now, and I'm very much in the above categories.
- CameronNemo 6y ago
  You may be an atypical case. Are you working in anything microkernel related?
  - PoignardAzur 6y ago
    No.

tyingq 6y ago

This covers some of that. https://fuchsia.googlesource.com/docs/+/refs/heads/sandbox/jschein/default/libc.md https://fuchsia.googlesource.com/docs/+/refs/heads/sandbox/j...

linuxftw 6y ago

Fuchsia's not a real thing and it's never going to be. You don't have to worry about it, it's just a make-work project for some people at google to feel cool.

dane-pgp 6y ago
More likely, Google have done threat modelling of their entire business and worked out that if there was ever some legal problem with using Linux (like the infamous SCO case), the amount of economic damage it would do to them would be more than whatever resources they are spending on coming up with an alternative (which will hopefully never need to be used). Also, just as Chrome gave them a seat at the table of web standardisation, and a chance to try new ideas that didn't have to go through Mozilla's approval process, having a kernel of their own allows them to influence the OS design space in ways that are more aligned to their business goals, and without needing Linus's approval.
- linuxftw 6y ago
  They can use BSD to build whatever they want if they're worried about the GPL. I think that someone at google built fuschia for the sake of building it. Their core business is still search, that's all Android is. If they launch their own fuschia based handset, people are unlikely to switch, OEMs are unlikely to switch. It's just a failed concept.
  - cycloptic 6y ago
    See some of the sibling comments, fuchsia is BSD-licensed and has a new design not based on any Unix.
    - linuxftw 6y ago
      I'm talking about BSD the operating system concerning the OP's assertion of managing risk. Last I checked (years ago), the userspace was implemented partially with musl, which reads > 'musl, pronounced like the word "mussel", is an MIT-licensed implementation of the standard C library targetting the Linux syscall API, Now, they're announcing running Linux programs on Fuchsia. Sure seems to me they're implementing a Unix-like system, even if their kernel was written from scratch. The BSD world doesn't consider the userspace very separate from the kernel space, it's all part of a single system. I would argue it's very much 'based on Unix' as soon as they start adding POSIX APIs. They're adding POSIX APIs because they work.

abarth 6y ago

The memory model is similar (a flat, linear address space). The OS APIs are quite different. Fuchsia's OS APIs are designed around an object-capability discipline. For example, almost all the syscalls take a zx_handle_t as their first argument, which means they are operations on an object the process has previously been granted access explicitly. In Linux, many OS APIs operate on the "ambient" environment rather than on a specific kernel object. Disclosure: I work on Fuchsia.

saagarjha 6y ago

It's fairly different; the OS is built on capabilities and exposing its system API via libc. By default applications get nothing. Resources are objects. IPC is done using a wire format called FIDL.

The_rationalist 6y ago
What does FIDl bring over d-bus or say mojo ?