class IO
Public Instance Methods
Returns number of bytes that can be read without blocking. Returns zero if no information available.
You must require ‘io/wait’ to use this method.
static VALUE
io_nread(VALUE io)
{
rb_io_t *fptr;
int len;
ioctl_arg n;
GetOpenFile(io, fptr);
rb_io_check_readable(fptr);
len = rb_io_read_pending(fptr);
if (len > 0) return INT2FIX(len);
#ifdef HAVE_RB_IO_DESCRIPTOR
int fd = rb_io_descriptor(io);
#else
int fd = fptr->fd;
#endif
if (!FIONREAD_POSSIBLE_P(fd)) return INT2FIX(0);
if (ioctl(fd, FIONREAD, &n)) return INT2FIX(0);
if (n > 0) return ioctl_arg2num(n);
return INT2FIX(0);
}
Returns a truthy value if input available without blocking, or a falsy value.
You must require ‘io/wait’ to use this method.
static VALUE
io_ready_p(VALUE io)
{
rb_io_t *fptr;
#ifndef HAVE_RB_IO_WAIT
struct timeval tv = {0, 0};
#endif
GetOpenFile(io, fptr);
rb_io_check_readable(fptr);
if (rb_io_read_pending(fptr)) return Qtrue;
#ifndef HAVE_RB_IO_WAIT
return wait_for_single_fd(fptr, RB_WAITFD_IN, &tv) ? Qtrue : Qfalse;
#else
return io_wait_event(io, RUBY_IO_READABLE, RB_INT2NUM(0), 1);
#endif
}
Waits until the IO becomes ready for the specified events and returns the subset of events that become ready, or a falsy value when times out.
The events can be a bit mask of IO::READABLE, IO::WRITABLE or IO::PRIORITY.
Returns a truthy value immediately when buffered data is available.
Optional parameter mode is one of :read, :write, or :read_write.
You must require ‘io/wait’ to use this method.
static VALUE
io_wait(int argc, VALUE *argv, VALUE io)
{
#ifndef HAVE_RB_IO_WAIT
rb_io_t *fptr;
struct timeval timerec;
struct timeval *tv = NULL;
int event = 0;
int i;
GetOpenFile(io, fptr);
for (i = 0; i < argc; ++i) {
if (SYMBOL_P(argv[i])) {
event |= wait_mode_sym(argv[i]);
}
else {
*(tv = &timerec) = rb_time_interval(argv[i]);
}
}
/* rb_time_interval() and might_mode() might convert the argument */
rb_io_check_closed(fptr);
if (!event) event = RB_WAITFD_IN;
if ((event & RB_WAITFD_IN) && rb_io_read_pending(fptr))
return Qtrue;
if (wait_for_single_fd(fptr, event, tv))
return io;
return Qnil;
#else
VALUE timeout = Qundef;
rb_io_event_t events = 0;
int i, return_io = 0;
/* The documented signature for this method is actually incorrect.
* A single timeout is allowed in any position, and multiple symbols can be given.
* Whether this is intentional or not, I don't know, and as such I consider this to
* be a legacy/slow path. */
if (argc != 2 || (RB_SYMBOL_P(argv[0]) || RB_SYMBOL_P(argv[1]))) {
/* We'd prefer to return the actual mask, but this form would return the io itself: */
return_io = 1;
/* Slow/messy path: */
for (i = 0; i < argc; i += 1) {
if (RB_SYMBOL_P(argv[i])) {
events |= wait_mode_sym(argv[i]);
}
else if (timeout == Qundef) {
rb_time_interval(timeout = argv[i]);
}
else {
rb_raise(rb_eArgError, "timeout given more than once");
}
}
if (timeout == Qundef) timeout = Qnil;
if (events == 0) {
events = RUBY_IO_READABLE;
}
}
else /* argc == 2 and neither are symbols */ {
/* This is the fast path: */
events = io_event_from_value(argv[0]);
timeout = argv[1];
}
if (events & RUBY_IO_READABLE) {
rb_io_t *fptr = NULL;
RB_IO_POINTER(io, fptr);
if (rb_io_read_pending(fptr)) {
/* This was the original behaviour: */
if (return_io) return Qtrue;
/* New behaviour always returns an event mask: */
else return RB_INT2NUM(RUBY_IO_READABLE);
}
}
return io_wait_event(io, events, timeout, return_io);
#endif
}
Waits until IO is priority and returns a truthy value or a falsy value when times out. Priority data is sent and received using the Socket::MSG_OOB flag and is typically limited to streams.
You must require ‘io/wait’ to use this method.
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, 1);
}
Waits until IO is readable and returns a truthy value, or a falsy value when times out. Returns a truthy value immediately when buffered data is available.
You must require ‘io/wait’ to use this method.
static VALUE
io_wait_readable(int argc, VALUE *argv, VALUE io)
{
rb_io_t *fptr;
#ifndef HAVE_RB_IO_WAIT
struct timeval timerec;
struct timeval *tv;
#endif
GetOpenFile(io, fptr);
rb_io_check_readable(fptr);
#ifndef HAVE_RB_IO_WAIT
tv = get_timeout(argc, argv, &timerec);
#endif
if (rb_io_read_pending(fptr)) return Qtrue;
#ifndef HAVE_RB_IO_WAIT
if (wait_for_single_fd(fptr, RB_WAITFD_IN, tv)) {
return io;
}
return Qnil;
#else
rb_check_arity(argc, 0, 1);
VALUE timeout = (argc == 1 ? argv[0] : Qnil);
return io_wait_event(io, RUBY_IO_READABLE, timeout, 1);
#endif
}
Waits until IO is writable and returns a truthy value or a falsy value when times out.
You must require ‘io/wait’ to use this method.
static VALUE
io_wait_writable(int argc, VALUE *argv, VALUE io)
{
rb_io_t *fptr;
#ifndef HAVE_RB_IO_WAIT
struct timeval timerec;
struct timeval *tv;
#endif
GetOpenFile(io, fptr);
rb_io_check_writable(fptr);
#ifndef HAVE_RB_IO_WAIT
tv = get_timeout(argc, argv, &timerec);
if (wait_for_single_fd(fptr, RB_WAITFD_OUT, tv)) {
return io;
}
return Qnil;
#else
rb_check_arity(argc, 0, 1);
VALUE timeout = (argc == 1 ? argv[0] : Qnil);
return io_wait_event(io, RUBY_IO_WRITABLE, timeout, 1);
#endif
}