cc -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations signal/sigwait.c -o signal/sigwait -D_POSIX_C_SOURCE=202405L -lm -lpthread -lrt -lintl -liconv
signal/sigwait.c:5:55: error: ‘sigwait’ undeclared here (not in a function)
    5 | int (*foo)(const sigset_t *restrict, int *restrict) = sigwait;
      |                                                       ^~~~~~~