write() Function

The write filter method is called when output data is to be sent. Filters that modify or consume outgoing data should implement the write filter method.

Upon receiving control, a write implementation should first process the data as necessary, and then pass it on to the next filter layer, for example, by calling net_write(layer->lower, ...,). If the filter buffers outgoing data, it should implement the flush filter method.

Syntax

int write(FilterLayer *layer, const void *buf, int amount);

Return Values

The number of bytes consumed, which might be less than the requested amount if an error occurred.

Parameters

FilterLayer *layer is the filter layer in which the filter is installed.

const void *buf is the buffer that contains the outgoing data.

int amount is the number of bytes in the buffer.

Example

int myfilter_write(FilterLayer *layer, const void *buf, int amount)
{
    return net_write(layer->lower, buf, amount);
}

See Also

flush() Function, net_write() Function, writev() Function, filter_create() Function