Gracias por la aclaración.
La forma más fácil de lograr lo que busca es ejecutar su script con el bucle dentro de un contenedor como el timeout
comando del paquete GNU Coreutils.
root@coraid-sp:~# timeout --help
Usage: timeout [OPTION] DURATION COMMAND [ARG]...
or: timeout [OPTION]
Start COMMAND, and kill it if still running after DURATION.
Mandatory arguments to long options are mandatory for short options too.
-k, --kill-after=DURATION
also send a KILL signal if COMMAND is still running
this long after the initial signal was sent.
-s, --signal=SIGNAL
specify the signal to be sent on timeout.
SIGNAL may be a name like 'HUP' or a number.
See `kill -l` for a list of signals
--help display this help and exit
--version output version information and exit
DURATION is an integer with an optional suffix:
`s' for seconds(the default), `m' for minutes, `h' for hours or `d' for days.
If the command times out, then exit with status 124. Otherwise, exit
with the status of COMMAND. If no signal is specified, send the TERM
signal upon timeout. The TERM signal kills any process that does not
block or catch that signal. For other processes, it may be necessary to
use the KILL (9) signal, since this signal cannot be caught.
Report timeout bugs to bug-coreutils@gnu.org
GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
General help using GNU software: <http://www.gnu.org/gethelp/>
For complete documentation, run: info coreutils 'timeout invocation'
Al final, será mucho más fácil que escribir su propia función de tiempo de espera, que las conchas tienden a no tener incorporado.