Tries to write the bytes contained in the n_vectors vectors into the stream. Will block during the operation.

If n_vectors is 0 or the sum of all bytes in vectors is 0, returns 0 and does nothing.

On success, the number of bytes written to the stream is returned. It is not an error if this is not the same as the requested size, as it can happen e.g. on a partial I/O error, or if there is not enough storage in the stream. All writes block until at least one byte is written or an error occurs; 0 is never returned (unless n_vectors is 0 or the sum of all bytes in vectors is 0).

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 G_IO_ERROR_CANCELLED will be returned. If an operation was partially finished when the operation was cancelled the partial result will be returned, without an error.

Some implementations of OutputStream.writev may have limitations on the aggregate buffer size, and will return G_IO_ERROR_INVALID_ARGUMENT if these are exceeded. For example, when writing to a local file on UNIX platforms, the aggregate buffer size must not exceed G_MAXSSIZE bytes.

class OutputStream


vectors GOutputVector[]

the buffer containing the GOutputVectors to write.

bytesWritten size_t

location to store the number of bytes that were written to the stream

cancellable Cancellable

optional cancellable object

Return Value

Type: bool

TRUE on success, FALSE if there was an error


GException on failure.