Tries to read a single byte from the stream or the buffer.
Will block during this read.
On success, the byte read from the stream is returned. On end of stream `-1` is returned but it's not an exceptional error and throws is not set.
If cancellable is not `NULL`, then the operation can be cancelled by triggering the cancellable object from another thread.
If the operation was cancelled, the error [error@Gio.IOErrorEnum.CANCELLED] will be returned. If an operation was partially finished when
the operation was cancelled the partial result will be returned, without an error.
On error `-1` is returned and throws is set accordingly.
| this |
a [class@Gio.BufferedInputStream] |
| cancellable |
optional [class@Gio.Cancellable] object, `NULL` to ignore |
|
the byte read from the this, or `-1` on end of stream or error. |