cc -pthread -Wall -Wextra -Werror=implicit-function-declaration semaphore/sem_clockwait.c -o semaphore/sem_clockwait -D_GNU_SOURCE -D_BSD_SOURCE -D_ALL_SOURCE -D_DEFAULT_SOURCE -lm -lpthread -lrt -lintl -lcrypt -latomic semaphore/sem_clockwait.c: In function 'main': semaphore/sem_clockwait.c:17:14: error: implicit declaration of function 'sem_clockwait'; did you mean 'sem_wait'? [-Wimplicit-function-declaration] 17 | if ( sem_clockwait(&sem, CLOCK_MONOTONIC, &long_timeout) < 0 ) | ^~~~~~~~~~~~~ | sem_wait