F_GETFL           484 os/unix/ngx_files.c     flags = fcntl(fd, F_GETFL);
F_GETFL           499 os/unix/ngx_files.c     flags = fcntl(fd, F_GETFL);
F_GETFL            32 os/unix/ngx_socket.h #define ngx_nonblocking(s)  fcntl(s, F_SETFL, fcntl(s, F_GETFL) | O_NONBLOCK)
F_GETFL            35 os/unix/ngx_socket.h #define ngx_blocking(s)     fcntl(s, F_SETFL, fcntl(s, F_GETFL) & ~O_NONBLOCK)