isReadable
Checks if @stream can be read.
Note that some stream types may not be able to implement this 100% reliably, and it is possible that a call to g_input_stream_read() after this returns true would still block. To guarantee non-blocking behavior, you should always use g_pollable_input_stream_read_nonblocking(), which will return a %G_IO_ERROR_WOULD_BLOCK error rather than blocking.
The behaviour of this method is undefined if g_pollable_input_stream_can_poll() returns false for @stream.
Return
true if @stream is readable, false if not. If an error has occurred on @stream, this will result in g_pollable_input_stream_is_readable() returning true, and the next attempt to read will return the error.
Since
2.28