I_FLUSHBAND streamio Operation

Purpose

Flushes all messages from a particular band.

Description

The I_FLUSHBAND operation flushes all messages of a given priority band from all input or output queues. The arg parameter points to a bandinfo structure that contains the following elements:

unsigned char   bi_pri;
int             bi_flag;

The elements are defined as follows:

Element Description
bi_pri Specifies the band to be flushed.
bi_flag Specifies the queues to be pushed. Legal values for the bi_flag field are:
FLUSHR
Flush read queues.
FLUSHW
Flush write queues.
FLUSHRW
Flush read and write queues.

This operation is part of STREAMS Kernel Extensions.

Error Codes

If unsuccessful, the errno global variable is set to one of the following values:

Value Description
ENOSR Unable to allocate buffers for flush message due to insufficient STREAMS memory resources.
EINVAL Invalid value for the arg parameter.
ENXIO Hangup received on the fildes parameter.