FLUSH(5) File Formats Manual FLUSH(5)
NAME
flush - abort a message
SYNOPSIS
Tflush tag[2] oldtag[2]
Rflush tag[2]
DESCRIPTION
When the response to a request is no longer needed, such as when a user interrupts a process doing a read(2), a Tflush request is sent to
the server to purge the pending response. The message being flushed is identified by oldtag. The semantics of flush depends on messages
arriving in order.
The server must answer the flush message immediately. If it recognizes oldtag as the tag of a pending transaction, it should abort any
pending response and discard that tag. In either case, it should respond with an Rflush echoing the tag (not oldtag) of the Tflush mes-
sage. A Tflush can never be responded to by an Rerror message.
When the client sends the Tflush, it should disregard all messages received with tag oldtag until the corresponding Rflush is received, at
which point oldtag may be recycled for subsequent messages.
Several exceptional conditions are handled correctly by the above specification: sending multiple flushes for a single tag, flushing a
Tflush, and flushing an invalid tag.
FLUSH(5)
