Smashing 
Hello
I try open mq_open.
mq = mq_open("/test_mq", O_CREAT| O_RDWR , 0644, &attr);
Still I have Error -1.
I use image nanopi-neo-core-qte-sd4g-20161213.img
I can not find the folder "mqueue" in the directory /proc/sys/fs/
thx