Why xddp-stream demo process could not be terminate by ctrl + C.

[孙世龙 via Xenomai]

Hi,
     I could run the xddp-stream demo process normally indeed.
     But when i intend to terminate the process by ctrl+c, nothing has
happened.
     The only way i found useful is to use the shell command(sudo killall
-9 xddp-stream) to terminate it.
     I*'m really confused.*
*     As per the source code of
xddp-stream(https://gitlab.denx.de/Xenomai/xenomai/-/blob/v3.0.9//demo/posix/cobalt/xddp-stream.c
<https://gitlab.denx.de/Xenomai/xenomai/-/blob/v3.0.9//demo/posix/cobalt/xddp-stream.c>),
there no api used to capture the ctrl+c signal.*
     Thank you for your attention.
     Look forward to hearing from you.