On Sun, May 11, 2014 at 12:04:31AM -0400, Luke Shumaker wrote:
At Sat, 10 May 2014 22:36:44 -0400, Dave Reisner wrote:
On Sat, May 10, 2014 at 10:22:07PM -0400, Luke Shumaker wrote:
+#HOST_NAME_MAX="$(printf '%s\n' '#include <limits.h>' 'HOST_NAME_MAX'|cpp -|sed -n '$p')"
No need to write the include as if this were a source file, just tell cpp about it directly:
cpp -I limits.h <<<HOST_NAME_MAX | ...
That doesn't work, but this does:
cpp -include limits.h <<<HOST_NAME_MAX | ...
I'd never had occasion to use that flag before, so thank you!
Ah, right. -I is for directories.
+HOST_NAME_MAX=64 +if [[ ${#machine_name} -gt "$HOST_NAME_MAX" ]]; then + machine_name="${machine_name:(-${HOST_NAME_MAX})}" + machine_name="${machine_name#-}"
I think this is worth warning about, since it might result in name clashes.
Is it any more likely to cause clashes than the existing machine name munging? 64 characters is a lot, and I figure that the end is the part that is most likely to change.
Oh, I see. You're trimming leading characters, not truncating. Alternatively, just hash the full path? Is the machine name really useful in any way other than to define a unique name for the build container?
What about passing '-q' to systemd-nspawn and not directing its stderr to /dev/null? That way the user gets a reasonably friendly "Failed to register machine: Machine '$machine_name' already exits", as well as a message for any other errors that may occur. IIRC, the reason stderr was directed to /dev/null was that at the time it was written, systemd-nspawn didn't have a '-q' flag.
Sounds good to me. The --quiet flag was added to systemd in v209. d