1 17ab44fc 2021-07-31 op .\" Copyright (c) 2021 Omar Polo <op@omarpolo.com>
  2 17ab44fc 2021-07-31 op .\"
  3 17ab44fc 2021-07-31 op .\" Permission to use, copy, modify, and distribute this software for any
  4 17ab44fc 2021-07-31 op .\" purpose with or without fee is hereby granted, provided that the above
  5 17ab44fc 2021-07-31 op .\" copyright notice and this permission notice appear in all copies.
  6 17ab44fc 2021-07-31 op .\"
  7 17ab44fc 2021-07-31 op .\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  8 17ab44fc 2021-07-31 op .\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  9 17ab44fc 2021-07-31 op .\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 10 17ab44fc 2021-07-31 op .\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 11 17ab44fc 2021-07-31 op .\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 12 17ab44fc 2021-07-31 op .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 13 17ab44fc 2021-07-31 op .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 14 17ab44fc 2021-07-31 op .\"
 15 17ab44fc 2021-07-31 op .Dd $Mdocdate: July 30 2021 $
 16 17ab44fc 2021-07-31 op .Dt 9P 7
 17 17ab44fc 2021-07-31 op .Os
 18 17ab44fc 2021-07-31 op .Sh NAME
 19 17ab44fc 2021-07-31 op .Nm 9P
 20 17ab44fc 2021-07-31 op .Nd Simple Distributed File System
 21 17ab44fc 2021-07-31 op .Sh DESCRIPTION
 22 17ab44fc 2021-07-31 op .Nm
 23 3d1d2398 2021-08-04 op is a protocol that implements a distributed file systems.
 24 17ab44fc 2021-07-31 op It provides primitives to manage
 25 17ab44fc 2021-07-31 op .Pq create, read, write and delete
 26 17ab44fc 2021-07-31 op sets of files remotely.
 27 17ab44fc 2021-07-31 op These files don't necessarily need to be actually stored on a disk,
 28 17ab44fc 2021-07-31 op they may be, for example, synthesise on demand from external sources.
 29 17ab44fc 2021-07-31 op .Pp
 30 17ab44fc 2021-07-31 op A client transmits requests
 31 17ab44fc 2021-07-31 op .Pq T-messages
 32 17ab44fc 2021-07-31 op to a server, which returns replies
 33 17ab44fc 2021-07-31 op .Pq R-messages
 34 17ab44fc 2021-07-31 op to the client.
 35 17ab44fc 2021-07-31 op The combined acts of transmitting a request of a particular type and
 36 17ab44fc 2021-07-31 op receiving a reply is called a transaction of that type.
 37 17ab44fc 2021-07-31 op .Pp
 38 3d1d2398 2021-08-04 op Each message consists of a sequence of bytes mostly grouped in one,
 39 3d1d2398 2021-08-04 op two or four integer fields transmitted in little-endian order
 40 17ab44fc 2021-07-31 op .Pq least significant byte first .
 41 17ab44fc 2021-07-31 op Data items of larger or variable lengths are represented by a two-byte
 42 17ab44fc 2021-07-31 op field specifying the length followed by the actual data.
 43 3d1d2398 2021-08-04 op The only exception to this rule are QIDs, thirteen byte long
 44 3d1d2398 2021-08-04 op objects, that are sent as-is.
 45 3d1d2398 2021-08-04 op .Pp
 46 3d1d2398 2021-08-04 op Text strings are represented with a two-byte count and the sequence of
 47 3d1d2398 2021-08-04 op UNICODE codepoints encoded in UTF-8.
 48 3d1d2398 2021-08-04 op Text strings in 9p are not NUL-terminated.
 49 17ab44fc 2021-07-31 op The NUL-terminator is illegal in all text strings and thus excluded
 50 17ab44fc 2021-07-31 op from paths, user names and so on.
 51 17ab44fc 2021-07-31 op .Pp
 52 17ab44fc 2021-07-31 op Fields are hereafter denoted as
 53 17ab44fc 2021-07-31 op .Bd -literal -offset indent
 54 17ab44fc 2021-07-31 op type[1] tag[2] fid[4]
 55 17ab44fc 2021-07-31 op .Ed
 56 17ab44fc 2021-07-31 op .Pp
 57 17ab44fc 2021-07-31 op to indicate that type is one byte long, tag two and fid four.
 58 17ab44fc 2021-07-31 op Strings are denoted as name[s] and are sent on the wire as
 59 17ab44fc 2021-07-31 op .Bd -literal -offset indent
 60 17ab44fc 2021-07-31 op length[2] string[length]
 61 17ab44fc 2021-07-31 op .Ed
 62 17ab44fc 2021-07-31 op .Pp
 63 17ab44fc 2021-07-31 op A qid, described later, is a 13-byte value that is sent on the wire as
 64 17ab44fc 2021-07-31 op .Bd -literal -offset indent
 65 17ab44fc 2021-07-31 op type[1] version[4] path[8]
 66 17ab44fc 2021-07-31 op .Ed
 67 3d1d2398 2021-08-04 op .Sh MESSAGE STRUCTURE
 68 17ab44fc 2021-07-31 op Every message has a header with the following fields:
 69 17ab44fc 2021-07-31 op .Bd -literal -offset indent
 70 17ab44fc 2021-07-31 op len[4] type[1] tag[2]
 71 17ab44fc 2021-07-31 op .Ed
 72 17ab44fc 2021-07-31 op .Pp
 73 17ab44fc 2021-07-31 op where len indicates the overall length of the message, including
 74 17ab44fc 2021-07-31 op itself; type is one byte indicating the type of the message and the
 75 3d1d2398 2021-08-04 op tag is a number choosen by the client that indicate uniquely the
 76 17ab44fc 2021-07-31 op request.
 77 3d1d2398 2021-08-04 op Then follows an optional body whose structure depends on the type of
 78 3d1d2398 2021-08-04 op the message.
 79 17ab44fc 2021-07-31 op .Pp
 80 17ab44fc 2021-07-31 op The message types are as follows:
 81 d3d4880e 2021-12-02 op .Pq the header is omitted for brevity
 82 17ab44fc 2021-07-31 op .Bl -tag -width versionxx
 83 17ab44fc 2021-07-31 op .It Ic version
 84 17ab44fc 2021-07-31 op Negotiate the version and maximum message size.
 85 17ab44fc 2021-07-31 op .Bd -literal
 86 3756a3df 2021-08-08 op msize[4] version[s]
 87 3756a3df 2021-08-08 op msize[4] version[s]
 88 17ab44fc 2021-07-31 op .Ed
 89 17ab44fc 2021-07-31 op .Pp
 90 17ab44fc 2021-07-31 op The
 91 17ab44fc 2021-07-31 op .Ic version
 92 17ab44fc 2021-07-31 op request must be the first message sent, and the client cannot issue
 93 d3d4880e 2021-12-02 op further requests until receiving the Rversion reply.
 94 17ab44fc 2021-07-31 op .Cm tag
 95 17ab44fc 2021-07-31 op should be
 96 17ab44fc 2021-07-31 op .Dv NOTAG
 97 3d1d2398 2021-08-04 op .Pq \-1 or 255 .
 98 17ab44fc 2021-07-31 op The client suggest a
 99 17ab44fc 2021-07-31 op .Cm msize
100 17ab44fc 2021-07-31 op .Pq the maximum size for packets
101 3d1d2398 2021-08-04 op and the protocol version used, the server replies with a
102 17ab44fc 2021-07-31 op .Cm msize
103 17ab44fc 2021-07-31 op smaller or equal to the one proposed by the client.
104 17ab44fc 2021-07-31 op The version string must always begin with the two character
105 17ab44fc 2021-07-31 op .Dq 9P .
106 17ab44fc 2021-07-31 op If the server don't understand the client required version, should
107 17ab44fc 2021-07-31 op reply with a Rversion using the version string
108 17ab44fc 2021-07-31 op .Dq unknown
109 17ab44fc 2021-07-31 op and not use a Rerror.
110 17ab44fc 2021-07-31 op .It Ic attach
111 17ab44fc 2021-07-31 op Populate the namespace
112 17ab44fc 2021-07-31 op .Bd -literal
113 3756a3df 2021-08-08 op fid[4] afid[4] uname[s] aname[s]
114 3756a3df 2021-08-08 op qid[13]
115 17ab44fc 2021-07-31 op .Ed
116 30d22cc7 2021-12-14 op .Pp
117 30d22cc7 2021-12-14 op The
118 30d22cc7 2021-12-14 op .Ic attach
119 30d22cc7 2021-12-14 op message binds the given
120 30d22cc7 2021-12-14 op .Ar fid
121 30d22cc7 2021-12-14 op to the root of the file tree identified by
122 30d22cc7 2021-12-14 op .Ar aname .
123 30d22cc7 2021-12-14 op .Ar uname
124 30d22cc7 2021-12-14 op identifies the user and
125 30d22cc7 2021-12-14 op .Ar afid
126 30d22cc7 2021-12-14 op specifies a fid previously established by an auth message, or the
127 30d22cc7 2021-12-14 op special
128 571a8138 2021-12-15 op .Dv NOFID
129 30d22cc7 2021-12-14 op value
130 30d22cc7 2021-12-14 op .Pq defined as (u32int)~0
131 30d22cc7 2021-12-14 op if the authentication is not required.
132 17ab44fc 2021-07-31 op .It Ic clunk
133 17ab44fc 2021-07-31 op Close fids.
134 17ab44fc 2021-07-31 op .Bd -literal
135 3756a3df 2021-08-08 op fid[4]
136 3756a3df 2021-08-08 op .Aq empty response
137 17ab44fc 2021-07-31 op .Ed
138 30d22cc7 2021-12-14 op .Pp
139 30d22cc7 2021-12-14 op Once a fid has been clunked
140 30d22cc7 2021-12-14 op .Pq closed
141 30d22cc7 2021-12-14 op it becomes
142 30d22cc7 2021-12-14 op .Dq free
143 30d22cc7 2021-12-14 op and the same value can be used for subsequential
144 30d22cc7 2021-12-14 op .Ic walk
145 30d22cc7 2021-12-14 op or
146 30d22cc7 2021-12-14 op .Ic attach
147 30d22cc7 2021-12-14 op requests.
148 30d22cc7 2021-12-14 op .Pp
149 30d22cc7 2021-12-14 op The actual file on the disk is not remove unless it was opened with the
150 30d22cc7 2021-12-14 op .Dv ORCLOSE
151 30d22cc7 2021-12-14 op flag.
152 17ab44fc 2021-07-31 op .It Ic error
153 30d22cc7 2021-12-14 op Return an error string.
154 17ab44fc 2021-07-31 op .Bd -literal
155 3756a3df 2021-08-08 op ename[s]
156 17ab44fc 2021-07-31 op .Ed
157 17ab44fc 2021-07-31 op .Pp
158 17ab44fc 2021-07-31 op The Rerror message is used to return an error string describing the
159 17ab44fc 2021-07-31 op failure of a request.
160 3756a3df 2021-08-08 op The
161 17ab44fc 2021-07-31 op .Cm tag
162 17ab44fc 2021-07-31 op indicates the failed request.
163 30d22cc7 2021-12-14 op .Pp
164 3756a3df 2021-08-08 op Note that there isn't a
165 3756a3df 2021-08-08 op .Ic Terror
166 30d22cc7 2021-12-14 op request for obvious reason and it's not possible for a server to reply to
167 30d22cc7 2021-12-14 op a
168 17ab44fc 2021-07-31 op .Ic Tversion
169 30d22cc7 2021-12-14 op or
170 30d22cc7 2021-12-14 op .Ic Tflush
171 3756a3df 2021-08-08 op using
172 3756a3df 2021-08-08 op .Ic Rerror .
173 17ab44fc 2021-07-31 op .It Ic flush
174 17ab44fc 2021-07-31 op Abort an ongoing operation.
175 17ab44fc 2021-07-31 op .Bd -literal
176 3756a3df 2021-08-08 op oldtag[2]
177 3756a3df 2021-08-08 op .Aq empty response
178 17ab44fc 2021-07-31 op .Ed
179 30d22cc7 2021-12-14 op .Pp
180 30d22cc7 2021-12-14 op Given the asynchronous nature of the protocol, the server may respond to
181 30d22cc7 2021-12-14 op the pending request before responding to the
182 30d22cc7 2021-12-14 op .Ic Tflush
183 30d22cc7 2021-12-14 op and is possible for a client to send multiple
184 30d22cc7 2021-12-14 op .Ic Tflush
185 30d22cc7 2021-12-14 op for the same operation.
186 30d22cc7 2021-12-14 op The client must wait to receive a corresponding
187 30d22cc7 2021-12-14 op .Ic Rflush
188 30d22cc7 2021-12-14 op before reusing
189 30d22cc7 2021-12-14 op .Ar oldtag
190 30d22cc7 2021-12-14 op for subsequent messages.
191 30d22cc7 2021-12-14 op .Pp
192 30d22cc7 2021-12-14 op If a response for
193 30d22cc7 2021-12-14 op .Ar oldtag
194 30d22cc7 2021-12-14 op is received before the
195 30d22cc7 2021-12-14 op .Ic Rflush
196 30d22cc7 2021-12-14 op reply, the client must assume that the operation was completed with success
197 30d22cc7 2021-12-14 op .Pq fid allocated, files created, ...
198 30d22cc7 2021-12-14 op If no response is received before the
199 30d22cc7 2021-12-14 op .Ic Rflush
200 30d22cc7 2021-12-14 op then the transaction is considered to have been successfully cancelled.
201 30d22cc7 2021-12-14 op .Pp
202 30d22cc7 2021-12-14 op Note that the tag of this request and the corresponding reply is NOT
203 30d22cc7 2021-12-14 op .Ar oldtag
204 30d22cc7 2021-12-14 op but a new tag value.
205 5ab50685 2021-08-08 op .It Ic walk
206 5ab50685 2021-08-08 op Traverse a file tree.
207 5ab50685 2021-08-08 op .Bd -literal
208 3756a3df 2021-08-08 op fid[4] newfid[4] nwname[2] nwname*(wname[s])
209 3756a3df 2021-08-08 op nwqid[2] nwqid*(qid[13])
210 5ab50685 2021-08-08 op .Ed
211 30d22cc7 2021-12-14 op .Pp
212 30d22cc7 2021-12-14 op The
213 30d22cc7 2021-12-14 op .Ar nwname
214 30d22cc7 2021-12-14 op components are walked in order starting from
215 30d22cc7 2021-12-14 op .Ar fid
216 30d22cc7 2021-12-14 op .Pq which must point to a directory
217 30d22cc7 2021-12-14 op and, if successful,
218 30d22cc7 2021-12-14 op .Ar newfid
219 30d22cc7 2021-12-14 op is associated to the reached file.
220 30d22cc7 2021-12-14 op .Pp
221 30d22cc7 2021-12-14 op It is possible for
222 30d22cc7 2021-12-14 op .Ar fid
223 30d22cc7 2021-12-14 op and
224 30d22cc7 2021-12-14 op .Ar newfid
225 30d22cc7 2021-12-14 op to be equal, in this case the fid is
226 30d22cc7 2021-12-14 op .Dq mutated ,
227 30d22cc7 2021-12-14 op otherwise
228 30d22cc7 2021-12-14 op .Ar newfid
229 30d22cc7 2021-12-14 op must be unused.
230 30d22cc7 2021-12-14 op As a special case, a walk of zero components duplicates the fid.
231 30d22cc7 2021-12-14 op .Pp
232 30d22cc7 2021-12-14 op If the first element cannot be walked for any reason an
233 30d22cc7 2021-12-14 op .Ic Rerror
234 30d22cc7 2021-12-14 op is returned.
235 30d22cc7 2021-12-14 op Otherwise,
236 30d22cc7 2021-12-14 op .Ic Rwalk
237 30d22cc7 2021-12-14 op is returned with a number of qids equal to the file viside by the walk.
238 30d22cc7 2021-12-14 op A client can thus detect a walk when that the replied
239 30d22cc7 2021-12-14 op .Ar nwqid
240 30d22cc7 2021-12-14 op number is not equal to the
241 30d22cc7 2021-12-14 op .Ar nwname
242 30d22cc7 2021-12-14 op field in the request.
243 30d22cc7 2021-12-14 op Only when walk return successfully
244 30d22cc7 2021-12-14 op .Ar newfid
245 30d22cc7 2021-12-14 op will be affected.
246 30d22cc7 2021-12-14 op .Pp
247 30d22cc7 2021-12-14 op A maximum of 16 component can be used per walk request.
248 021481ca 2021-12-13 op .It Ic open
249 30d22cc7 2021-12-14 op Prepare a fid for I/O.
250 021481ca 2021-12-13 op .Bd -literal
251 021481ca 2021-12-13 op fid[4] mode[1]
252 021481ca 2021-12-13 op qid[13] iounit[4]
253 021481ca 2021-12-13 op .Ed
254 30d22cc7 2021-12-14 op .Pp
255 30d22cc7 2021-12-14 op .Ar mode
256 30d22cc7 2021-12-14 op determines the type of I/O:
257 30d22cc7 2021-12-14 op .Bl -tag -width Ds -offset indent -compact
258 571a8138 2021-12-15 op .It 0 Dv OREAD
259 571a8138 2021-12-15 op .It 1 Dv OWRITE
260 571a8138 2021-12-15 op .It 2 Dv ORDWD
261 571a8138 2021-12-15 op .It 3 Dv OEXEC
262 17ab44fc 2021-07-31 op .El
263 30d22cc7 2021-12-14 op .Pp
264 30d22cc7 2021-12-14 op The returned
265 30d22cc7 2021-12-14 op .Ar iounit
266 30d22cc7 2021-12-14 op is the optimal blocksize for I/O.
267 10447aa7 2021-12-20 op .It Ic create
268 10447aa7 2021-12-20 op Create a file
269 10447aa7 2021-12-20 op .Bd -literal
270 10447aa7 2021-12-20 op fid[4] name[s] perm[4] mode[1]
271 10447aa7 2021-12-20 op qid[13] iounit[4]
272 10447aa7 2021-12-20 op .Ed
273 10447aa7 2021-12-20 op .Pp
274 10447aa7 2021-12-20 op The call attempts to create a file named
275 10447aa7 2021-12-20 op .Ar name
276 10447aa7 2021-12-20 op in the directory identified by
277 10447aa7 2021-12-20 op .Ar fid
278 10447aa7 2021-12-20 op according to
279 10447aa7 2021-12-20 op .Ar perm
280 10447aa7 2021-12-20 op and then to open it with
281 10447aa7 2021-12-20 op .Ar mode
282 10447aa7 2021-12-20 op into the given
283 10447aa7 2021-12-20 op .Ar fid .
284 10447aa7 2021-12-20 op .Pp
285 10447aa7 2021-12-20 op It is illegal to use an already opened
286 369e8fb7 2021-12-21 op .Ar fid
287 369e8fb7 2021-12-21 op or to attempt to create the
288 369e8fb7 2021-12-21 op .Dq \&.
289 369e8fb7 2021-12-21 op or
290 369e8fb7 2021-12-21 op .Dq ..
291 369e8fb7 2021-12-21 op entries.
292 571a8138 2021-12-15 op .It Ic read
293 571a8138 2021-12-15 op Read data at offset from file
294 571a8138 2021-12-15 op .Bd -literal
295 571a8138 2021-12-15 op fid[4] offset[8] count[4]
296 571a8138 2021-12-15 op count[4] data[count]
297 571a8138 2021-12-15 op .Ed
298 571a8138 2021-12-15 op .Pp
299 571a8138 2021-12-15 op .Ar fid
300 571a8138 2021-12-15 op must have been prepared for I/O with a previous
301 571a8138 2021-12-15 op .Ic open
302 571a8138 2021-12-15 op call.
303 571a8138 2021-12-15 op The returned
304 571a8138 2021-12-15 op .Ar count
305 571a8138 2021-12-15 op is zero when reaching end-of-file and may be lesser than what requested.
306 571a8138 2021-12-15 op .Pp
307 571a8138 2021-12-15 op Directories are a stream of stat structures, as described in
308 571a8138 2021-12-15 op .Ic stat ,
309 571a8138 2021-12-15 op and for them the read request message must have offset equal to zero or
310 571a8138 2021-12-15 op the value of
311 571a8138 2021-12-15 op .Ar offset
312 571a8138 2021-12-15 op in the previous read on the directory plus the number of bytes returned
313 571a8138 2021-12-15 op in the previous read.
314 82a5db3f 2021-12-16 op Thus, is not possible to seek into directories except for rewinding.
315 82a5db3f 2021-12-16 op .It Ic write
316 82a5db3f 2021-12-16 op Write data at offset
317 82a5db3f 2021-12-16 op .Bd -literal
318 82a5db3f 2021-12-16 op fid[4] offset[8] count[4] data[count]
319 82a5db3f 2021-12-16 op count[4]
320 82a5db3f 2021-12-16 op .Ed
321 571a8138 2021-12-15 op .It Ic stat
322 571a8138 2021-12-15 op get file status
323 571a8138 2021-12-15 op .Bd -literal
324 571a8138 2021-12-15 op fid[4]
325 571a8138 2021-12-15 op stat[n]
326 571a8138 2021-12-15 op .Ed
327 571a8138 2021-12-15 op .Pp
328 571a8138 2021-12-15 op The stat structure is made by the following fields:
329 571a8138 2021-12-15 op .Bl -tag -width twelveletters -compact
330 571a8138 2021-12-15 op .It size[2]
331 571a8138 2021-12-15 op total byte count of the following data
332 571a8138 2021-12-15 op .It type[2]
333 571a8138 2021-12-15 op for kernel use
334 571a8138 2021-12-15 op .It dev[4]
335 571a8138 2021-12-15 op for kernel use
336 571a8138 2021-12-15 op .It qid[13]
337 571a8138 2021-12-15 op server unique identifier of the file
338 571a8138 2021-12-15 op .It mode[4]
339 571a8138 2021-12-15 op permissions and flags
340 571a8138 2021-12-15 op .It atime[4]
341 571a8138 2021-12-15 op last access time
342 571a8138 2021-12-15 op .It mtime[4]
343 571a8138 2021-12-15 op last modification time
344 571a8138 2021-12-15 op .It length[8]
345 571a8138 2021-12-15 op length of file in bytes
346 571a8138 2021-12-15 op .It name[s]
347 571a8138 2021-12-15 op file name
348 571a8138 2021-12-15 op (must be
349 571a8138 2021-12-15 op .Dq /
350 571a8138 2021-12-15 op if the file is the root directory of the server)
351 6b87cac6 2021-12-16 op .It uid[s]
352 6b87cac6 2021-12-16 op owner name
353 6b87cac6 2021-12-16 op .It gid[s]
354 6b87cac6 2021-12-16 op group name
355 6b87cac6 2021-12-16 op .It muid[s]
356 6b87cac6 2021-12-16 op name of the user who last modified the file.
357 30d22cc7 2021-12-14 op .El
358 10447aa7 2021-12-20 op .It Ic remove
359 10447aa7 2021-12-20 op Remove a file
360 10447aa7 2021-12-20 op .Bd -literal
361 10447aa7 2021-12-20 op fid[4]
362 10447aa7 2021-12-20 op .Aq empty response
363 571a8138 2021-12-15 op .Ed
364 571a8138 2021-12-15 op .El
365 c555879e 2021-12-21 op .\" .Sh 9P2000.L EXTENSIONS
366 c555879e 2021-12-21 op .\" .Xr kamid 8
367 c555879e 2021-12-21 op .\" supports also a subset of the
368 c555879e 2021-12-21 op .\" .Sq 9P2000.L
369 c555879e 2021-12-21 op .\" dialect.
370 c555879e 2021-12-21 op .\" The supported messages are
371 c555879e 2021-12-21 op .\" .Bl -tag -width readdir
372 c555879e 2021-12-21 op .\" .It Ic readdir
373 c555879e 2021-12-21 op .\" Read directory entries
374 c555879e 2021-12-21 op .\" .Bd -literal
375 c555879e 2021-12-21 op .\" fid[4] offset[8] count[4]
376 c555879e 2021-12-21 op .\" count[4] data[count]
377 c555879e 2021-12-21 op .\" .Ed
378 c555879e 2021-12-21 op .\" .Pp
379 c555879e 2021-12-21 op .\" Each directory entry is described by a variable-length record:
380 c555879e 2021-12-21 op .\" .Ql qid[13] offset[8] type[1] name[s] .
381 c555879e 2021-12-21 op .\" Offset is zero upon the first call.
382 c555879e 2021-12-21 op .\" If the
383 c555879e 2021-12-21 op .\" .Ar count
384 c555879e 2021-12-21 op .\" field in the
385 c555879e 2021-12-21 op .\" .Ic Rreaddir
386 c555879e 2021-12-21 op .\" response is not zero then more data is available.
387 c555879e 2021-12-21 op .\" .Pp
388 c555879e 2021-12-21 op .\" .Ar count
389 c555879e 2021-12-21 op .\" is allowed to be zero in the request.
390 c555879e 2021-12-21 op .\" .El
391 17ab44fc 2021-07-31 op .Sh SEE ALSO
392 17ab44fc 2021-07-31 op .Xr utf8 7 ,
393 17ab44fc 2021-07-31 op .Xr kamid 8