Would also recommend using commands like:

echo '#include <sys/syscall.h>' | gcc -E -dM -xc - | grep -i "read"

To get the real values on your PC to make sure.

I had LLMs give wrong numbers or constant definitions several times but getting it to generate a command like this and seeing it for myself works every time.

Also chromium docs has a table:

https://www.chromium.org/chromium-os/developer-library/refer...

It would be very useful to just make this website directly link to the syscall number.