ATTACH(5)
NAME
attach and nop − messages to initiate activity
SYNOPSIS
Tnop tag[2]
Rnop tag[2]
Tattach tag[2] fid[2] uid[28] aname[28]
Rattach tag[2] fid[2] qid[8]
DESCRIPTION
The nop request does nothing overt but may be used to synchronize the channel initially.
The tag should be notag (value 16rFFFF) for a nop message.
The attach message serves as a fresh introduction from a user on the client machine to a server. The message identifies the user (uid) and may select the file tree to access (aname).
As a result of the attach transaction, the client will have a connection to the root directory of the desired file tree, represented by fid. An error is returned if fid is already in use. The server’s idea of the root of the file tree is represented by the returned qid.
ENTRY POINTS
An attach transaction will be generated for kernel devices (see intro(3)). when a system call evaluates a file name beginning with #. A mount call (see sys-bind(2)) generates an attach message to the remote file server. When the kernel boots, an attach is made to the root device, root(3), and then an attach is made to the requested file server machine.