cc -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations time/pid_t.c -o time/pid_t -D_POSIX_C_SOURCE=202405L  -lm -lpthread  -liconv
time/pid_t.c:3:1: error: unknown type name 'pid_t'
    3 | pid_t* foo;
      | ^
1 error generated.