rb_fd_dup 318 include/ruby/intern.h void rb_fd_dup(rb_fdset_t *dst, const rb_fdset_t *src); rb_fd_dup 3583 thread.c rb_fd_dup(dst, src); rb_fd_dup 3639 thread.c ((fds1) ? rb_fd_dup(fds1, fds2) : (void)0)