Object
Returns number of bytes that can be read without blocking. Returns zero if no information available.
static VALUE io_nread(VALUE io) { rb_io_t *fptr = NULL; ioctl_arg n; GetOpenFile(io, fptr); rb_io_check_readable(fptr); int len = rb_io_read_pending(fptr); if (len > 0) return INT2FIX(len); if (!FIONREAD_POSSIBLE_P(fptr->fd)) return INT2FIX(0); if (ioctl(fptr->fd, FIONREAD, &n)) return INT2FIX(0); if (n > 0) return ioctl_arg2num(n); return INT2FIX(0); }
Returns true
if input available without blocking, or
false
.
static VALUE io_ready_p(VALUE io) { rb_io_t *fptr; GetOpenFile(io, fptr); rb_io_check_readable(fptr); if (rb_io_read_pending(fptr)) return Qtrue; return io_wait_event(io, RUBY_IO_READABLE, RB_INT2NUM(0)); }
Waits until the IO becomes ready for the specified
events and returns the subset of events that become ready, or
false
when times out.
The events can be a bit mask of IO::READABLE
,
IO::WRITABLE
or IO::PRIORITY
.
Returns true
immediately when buffered data is available.
Optional parameter mode
is one of :read
,
:write
, or :read_write
(deprecated).
static VALUE io_wait(int argc, VALUE *argv, VALUE io) { VALUE timeout = Qnil; rb_io_event_t events = 0; if (argc < 2 || (argc >= 2 && RB_SYMBOL_P(argv[1]))) { if (argc > 0) { timeout = argv[0]; } for (int i = 1; i < argc; i += 1) { events |= wait_mode_sym(argv[i]); } } else if (argc == 2) { events = RB_NUM2UINT(argv[0]); if (argv[1] != Qnil) { timeout = argv[1]; } } else { // TODO error return Qnil; } if (events == 0) { events = RUBY_IO_READABLE; } if (events & RUBY_IO_READABLE) { rb_io_t *fptr = NULL; RB_IO_POINTER(io, fptr); if (rb_io_read_pending(fptr)) { return Qtrue; } } return io_wait_event(io, events, timeout); }
Waits until IO is priority and returns
true
or false
when times out.
static VALUE io_wait_priority(int argc, VALUE *argv, VALUE io) { rb_io_t *fptr = NULL; RB_IO_POINTER(io, fptr); rb_io_check_readable(fptr); if (rb_io_read_pending(fptr)) return Qtrue; rb_check_arity(argc, 0, 1); VALUE timeout = argc == 1 ? argv[0] : Qnil; return io_wait_event(io, RUBY_IO_PRIORITY, timeout); }
Waits until IO is readable and returns
true
, or false
when times out. Returns
true
immediately when buffered data is available.
static VALUE io_wait_readable(int argc, VALUE *argv, VALUE io) { rb_io_t *fptr = NULL; RB_IO_POINTER(io, fptr); rb_io_check_readable(fptr); if (rb_io_read_pending(fptr)) return Qtrue; rb_check_arity(argc, 0, 1); VALUE timeout = (argc == 1 ? argv[0] : Qnil); return io_wait_event(io, RUBY_IO_READABLE, timeout); }
Waits until IO is writable and returns
true
or false
when times out.
static VALUE io_wait_writable(int argc, VALUE *argv, VALUE io) { rb_io_t *fptr = NULL; RB_IO_POINTER(io, fptr); rb_io_check_writable(fptr); rb_check_arity(argc, 0, 1); VALUE timeout = (argc == 1 ? argv[0] : Qnil); return io_wait_event(io, RUBY_IO_WRITABLE, timeout); }