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; 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); 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. Returns nil if no information available.
static VALUE io_ready_p(VALUE io) { rb_io_t *fptr; struct timeval tv = {0, 0}; GetOpenFile(io, fptr); rb_io_check_readable(fptr); if (rb_io_read_pending(fptr)) return Qtrue; if (wait_for_single_fd(fptr, RB_WAITFD_IN, &tv)) return Qtrue; return Qfalse; }
Waits until IO is readable or writable without
blocking and returns self
, or nil
when times out.
Returns true
immediately when buffered data is available.
Optional parameter mode
is one of :read
,
:write
, or :read_write
.
static VALUE io_wait_readwrite(int argc, VALUE *argv, VALUE io) { 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; }
Waits until IO is readable without blocking and
returns self
, or nil
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; struct timeval timerec; struct timeval *tv; GetOpenFile(io, fptr); rb_io_check_readable(fptr); tv = get_timeout(argc, argv, &timerec); if (rb_io_read_pending(fptr)) return Qtrue; if (wait_for_single_fd(fptr, RB_WAITFD_IN, tv)) { return io; } return Qnil; }
Waits until IO is writable without blocking and
returns self
or nil
when times out.
static VALUE io_wait_writable(int argc, VALUE *argv, VALUE io) { rb_io_t *fptr; struct timeval timerec; struct timeval *tv; GetOpenFile(io, fptr); rb_io_check_writable(fptr); tv = get_timeout(argc, argv, &timerec); if (wait_for_single_fd(fptr, RB_WAITFD_OUT, tv)) { return io; } return Qnil; }