readBytesAsync
Request an asynchronous read of @count bytes from the stream into a new #GBytes. When the operation is finished @callback will be called. You can then call g_input_stream_read_bytes_finish() to get the result of the operation.
During an async request no other sync and async calls are allowed on @stream, and will result in %G_IO_ERROR_PENDING errors.
A value of @count larger than %G_MAXSSIZE will cause a %G_IO_ERROR_INVALID_ARGUMENT error.
On success, the new #GBytes will be passed to the callback. It is not an error if this is smaller than the requested size, as it can happen e.g. near the end of a file, but generally we try to read as many bytes as requested. Zero is returned on end of file (or if
Since
2.34
Parameters
the number of bytes that will be read from the stream
the io-priority of the request
optional #GCancellable object, null to ignore.
callback to call when the request is satisfied