cc -pthread  -Wall -Wextra -Werror=implicit-function-declaration pthread/pthread_setschedprio.c -o pthread/pthread_setschedprio -D_GNU_SOURCE -D_BSD_SOURCE -D_ALL_SOURCE -D_DEFAULT_SOURCE  -lm -lpthread  -liconv
pthread/pthread_setschedprio.c:20:16: error: call to undeclared function 'pthread_setschedprio'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
   20 |         if ( (errno = pthread_setschedprio(pthread_self(), priority)) /*&&
      |                       ^
pthread/pthread_setschedprio.c:20:16: note: did you mean 'pthread_setschedparam'?
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/pthread.h:510:5: note: 'pthread_setschedparam' declared here
  510 | int pthread_setschedparam(pthread_t, int, const struct sched_param *);
      |     ^
1 error generated.