timeout

[ckohrt]

timeout

[andig]

/cc @r00t-

[r00t-]

@ckohrt:
i'm not sure if this within the scope of libsml...

sml_server is a simple program intended to demonstrate the use of the library (it lives in an "examples" directory).
sml_server uses some simple i/o utility functions that libsml provides in sml_trasport.[ch],
which use blocking i/o and do not support timeouts.
i'd say, you are very welcome to write your own program using libsml that implements more advanced semantics.
by replacing sml_transport_listen() and sml_transport_read() with your own code, and passing the data to sml_transport_receiver().
we might want to offer a more flexible variant of sml_transport_read() that can be used with non-blocking io, or otherwise provide the scanning for start sequence and reading of a datagram in a more generic interface.
but as stated above, now sure if this is within scope,
it would also mean an ABI change.

why are you not using vzlogger?
it can read multiple meters in a single process and forward the data to your processing of choice.

as an alternative, if you insist on scripting around sml_server, have you considered simply wrapping sml_server in https://www.gnu.org/software/coreutils/timeout ?

[ckohrt]

hi @r00t-!
Thank you very much. I ended up with:

Z_1_182=$(timeout --foreground 10 /usr/bin/sml_server /dev/zaehler_1 | head -n10 | grep -oP '1\.8\.2\*255#\K.*(?=#)')

which works. Of course vzlogger is a better alternative, but I didn't want to get vzlogger running on my raspberry as I already have a working solution. It's just the time invest.... and with the timeout solution it works nearly without any time invest!

Big thanks!
Christian

[r00t-]

@ckohrt:
--foreground should not be necessary.

[ckohrt]

@ckohrt: --foreground should not be necessary.

Thanks!

[ckohrt]

Solution:
Z_1_182=$(timeout 10 /usr/bin/sml_server /dev/zaehler_1 | head -n10 | grep -oP '1\.8\.2\*255#\K.*(?=#)')