3 ms·

Shared / Open source is super helpful when you're trying to figure out how to do something unusual that's not on the paved path covered by the docs and examples

Shared / Open source is super helpful when you're trying to figure out how to do something unusual that's not on the paved path covered by the docs and examples. In the early 2000s, when doing Mac drivers for an OS-bypass HPC NIC (Myrinet, a sort of pre-cursor to inifiband/roce), I spent 90% of my time reading the Apple source and about 10% of my time coding. In my case the first goal was to figure out how to use BSD ioctls rather than Mach based userclient stuff, as we had tons of shared kernel and userspace code for ioctls (across linux, dec unix, solaris, freebsd, windows, etc). And the second was figuring out exactly which iomemory descriptor variant would work well for registering memory.

jamesfmilne 4y ago
Interesting background. I've recently been toying with the idea of writing some open-source Mac DriverKit drivers for Mellanox cards, so I'm not forced to pay through the nose for ATTO cards (which are just rebranded Mellanox cards.) Sadly all the DriverKit stuff appears to be completely closed source. At least its user-space though, so perhaps a bit less painful than normal kernel driver development...
ignoramous 4y ago
> Shared / Open source is super helpful when you're trying to figure out how to do something unusual that's not on the paved path covered by the docs and examples. Not just the unusual, but the usual too: Just this past month or so, a user on Fly.io forums helped debug just why reading from stdin / writing to stdout didn't work for non-root users (https://community.fly.io/t/10375/8 https://community.fly.io/t/10375/8). It all started from the fact that Fly.io had open sourced a snapshot-in-time of their init process back in 2021. Also, it isn't uncommon in the Android world for developers to routinely find the right APIs to use by reading the OS source code.
- iudqnolq 4y ago
  A very meaningful point in my learning as a junior developer was when I realized I should regularly click go to definition on standard library functions. I needed to tweak the behavior of an Android standard library function, so I copied it's source code (~20 lines) and made some edits. Blew my mind at the time it was that simple.
  - deleted 4y ago
    [deleted]
thayne 4y ago
On the flip side of that, I've recently had to deal with a few issues with some proprietary software, where it would have been really, really useful to be able to look through the source code, but I couldn't. Instead I had to rely on incomplete documentation, and customer support that didn't have enough technical knowledge to fully understand the problem.

jamesfmilne 4y ago

Interesting background. I've recently been toying with the idea of writing some open-source Mac DriverKit drivers for Mellanox cards, so I'm not forced to pay through the nose for ATTO cards (which are just rebranded Mellanox cards.) Sadly all the DriverKit stuff appears to be completely closed source. At least its user-space though, so perhaps a bit less painful than normal kernel driver development...

ignoramous 4y ago

> Shared / Open source is super helpful when you're trying to figure out how to do something unusual that's not on the paved path covered by the docs and examples. Not just the unusual, but the usual too: Just this past month or so, a user on Fly.io forums helped debug just why reading from stdin / writing to stdout didn't work for non-root users (https://community.fly.io/t/10375/8 https://community.fly.io/t/10375/8). It all started from the fact that Fly.io had open sourced a snapshot-in-time of their init process back in 2021. Also, it isn't uncommon in the Android world for developers to routinely find the right APIs to use by reading the OS source code.

iudqnolq 4y ago
A very meaningful point in my learning as a junior developer was when I realized I should regularly click go to definition on standard library functions. I needed to tweak the behavior of an Android standard library function, so I copied it's source code (~20 lines) and made some edits. Blew my mind at the time it was that simple.
- deleted 4y ago
  [deleted]

thayne 4y ago

On the flip side of that, I've recently had to deal with a few issues with some proprietary software, where it would have been really, really useful to be able to look through the source code, but I couldn't. Instead I had to rely on incomplete documentation, and customer support that didn't have enough technical knowledge to fully understand the problem.