x86_64-managarm-gcc -pthread   -Wall -Wextra -Werror=implicit-function-declaration mqueue/mq_notify.c -o mqueue/mq_notify -D_GNU_SOURCE -D_BSD_SOURCE -D_ALL_SOURCE -D_DEFAULT_SOURCE -lm -lpthread -lrt  -lintl -liconv -lintl -liconv
mqueue/mq_notify.c: In function ‘main’:
mqueue/mq_notify.c:120:14: error: implicit declaration of function ‘mq_notify’ [-Wimplicit-function-declaration]
  120 |         if ( mq_notify(mq, &sevsig) < 0 )
      |              ^~~~~~~~~
mqueue/mq_notify.c:134:14: error: implicit declaration of function ‘mq_send’ [-Wimplicit-function-declaration]
  134 |         if ( mq_send(mq, "foo", 3, 0) < 0 )
      |              ^~~~~~~