linux OS return value

Question

When Berkeley db updates some items using db.put(), it return 28, and I go through the doc of bdb, find out that if return value > 0, it's a system error, not from bdb per se.

But where can I find out what this system error (exit code 28) mean?

Answer 1

from the file errno.h on your machine (there are usually several files, so follow the #include trail)

    #define ENOSPC          28      /* No space left on device */