g_pollable_output_stream_write_nonblocking (
  GPollableOutputStream* stream,
  void* buffer,
  gsize count,
  GCancellable* cancellable,
  GError** error


Attempts to write up to count bytes from buffer to stream, as with g_output_stream_write(). If stream is not currently writable, this will immediately return G_IO_ERROR_WOULD_BLOCK, and you can use g_pollable_output_stream_create_source() to create a GSource that will be triggered when stream is writable.

Note that since this method never blocks, you cannot actually use cancellable to cancel it. However, it will return an error if cancellable has already been cancelled when you call, which may happen if you call this method after a source triggers due to having been cancelled.

Also note that if G_IO_ERROR_WOULD_BLOCK is returned some underlying transports like D/TLS require that you re-send the same buffer and count in the next write call.

The behaviour of this method is undefined if g_pollable_output_stream_can_poll() returns FALSE for stream.



Type: An array of guint8

A buffer to write data from.

The length of the array is specified in the count argument.
The data is owned by the caller of the function.

Type: gsize

The number of bytes you want to write.


Type: GCancellable

A GCancellable, or NULL.

The argument can be NULL.
The data is owned by the caller of the function.

Type: GError **

The return location for a recoverable error.

The argument can be NULL.
If the return location is not NULL, then you must initialize it to a NULL GError*.
The argument will left initialized to NULL by the method if there are no errors.
In case of error, the argument will be set to a newly allocated GError; the caller will take ownership of the data, and be responsible for freeing it.

Return value

Type: gssize

The number of bytes written, or -1 on error (including G_IO_ERROR_WOULD_BLOCK).