1 058b0118 2005-01-03 devnull .TH 9PCLIENT 3
  2 058b0118 2005-01-03 devnull .SH NAME
  3 058b0118 2005-01-03 devnull CFid, CFsys, fsinit, fsmount, fsroot, fssetroot, fsunmount, nsmount, fsversion, fsauth, fsattach, fsclose, fscreate, fsdirread, fsdirreadall, fsdirstat, fsdirfstat, fsdirwstat, fsdirfwstat, fsopen, fsopenfd, fspread, fspwrite, fsread, fsreadn, fswrite \- 9P client library
  4 058b0118 2005-01-03 devnull .SH SYNOPSIS
  5 058b0118 2005-01-03 devnull .B #include <u.h>
  6 058b0118 2005-01-03 devnull .PP
  7 058b0118 2005-01-03 devnull .B #include <libc.h>
  8 058b0118 2005-01-03 devnull .PP
  9 058b0118 2005-01-03 devnull .B #include <fcall.h>
 10 058b0118 2005-01-03 devnull .PP
 11 058b0118 2005-01-03 devnull .B #include <9pclient.h>
 12 c8b6342d 2005-01-13 devnull .ta +\w'\fLCFsys* 'u
 13 058b0118 2005-01-03 devnull .PP
 14 058b0118 2005-01-03 devnull .B
 15 058b0118 2005-01-03 devnull CFsys*	fsmount(int fd, char *aname)
 16 058b0118 2005-01-03 devnull .PP
 17 058b0118 2005-01-03 devnull .B
 18 058b0118 2005-01-03 devnull CFsys*	nsmount(char *name, char *aname)
 19 058b0118 2005-01-03 devnull .PP
 20 058b0118 2005-01-03 devnull .B
 21 058b0118 2005-01-03 devnull CFid*	fsroot(CFsys *fsys)
 22 058b0118 2005-01-03 devnull .PP
 23 058b0118 2005-01-03 devnull .B
 24 058b0118 2005-01-03 devnull void	fsunmount(CFsys *fsys)
 25 058b0118 2005-01-03 devnull .PP
 26 058b0118 2005-01-03 devnull .B
 27 058b0118 2005-01-03 devnull CFsys*	fsinit(int fd)
 28 058b0118 2005-01-03 devnull .PP
 29 058b0118 2005-01-03 devnull .B
 30 058b0118 2005-01-03 devnull int	fsversion(CFsys *fsys, int msize, char *version, int nversion)
 31 058b0118 2005-01-03 devnull .PP
 32 058b0118 2005-01-03 devnull .B
 33 058b0118 2005-01-03 devnull CFid	*fsauth(CFsys *fsys, char *uname, char *aname)
 34 058b0118 2005-01-03 devnull .PP
 35 058b0118 2005-01-03 devnull .B
 36 058b0118 2005-01-03 devnull CFid	*fsattach(CFsys *fsys, CFid *afid, char *uname, char *aname)
 37 058b0118 2005-01-03 devnull .PP
 38 058b0118 2005-01-03 devnull .B
 39 058b0118 2005-01-03 devnull void	fssetroot(CFsys *fsys, CFid *fid)
 40 058b0118 2005-01-03 devnull .PP
 41 058b0118 2005-01-03 devnull .B
 42 058b0118 2005-01-03 devnull void	fsclose(CFid *fid)
 43 058b0118 2005-01-03 devnull .PP
 44 058b0118 2005-01-03 devnull .B
 45 058b0118 2005-01-03 devnull CFid	*fscreate(CFsys *fs, char *path, int mode, ulong perm)
 46 058b0118 2005-01-03 devnull .PP
 47 058b0118 2005-01-03 devnull .B
 48 058b0118 2005-01-03 devnull CFid*	fsopen(CFsys *fs, char *path, int mode)
 49 058b0118 2005-01-03 devnull .PP
 50 058b0118 2005-01-03 devnull .B
 51 058b0118 2005-01-03 devnull long	fspread(CFid *fid, void *buf, long n, vlong offset)
 52 058b0118 2005-01-03 devnull .PP
 53 058b0118 2005-01-03 devnull .B
 54 058b0118 2005-01-03 devnull long	fspwrite(CFid *fid, void *buf, long n, vlong offset)
 55 058b0118 2005-01-03 devnull .PP
 56 058b0118 2005-01-03 devnull .B
 57 058b0118 2005-01-03 devnull long	fsread(CFid *fid, void *buf, long n)
 58 058b0118 2005-01-03 devnull .PP
 59 058b0118 2005-01-03 devnull .B
 60 058b0118 2005-01-03 devnull long	fsreadn(CFid *fid, void *buf, long n)
 61 058b0118 2005-01-03 devnull .PP
 62 058b0118 2005-01-03 devnull .B
 63 058b0118 2005-01-03 devnull long	fswrite(CFid *fid, void *buf, long n)
 64 058b0118 2005-01-03 devnull .PP
 65 058b0118 2005-01-03 devnull .B
 66 058b0118 2005-01-03 devnull long	fsdirread(CFid *fid, Dir **d)
 67 058b0118 2005-01-03 devnull .PP
 68 058b0118 2005-01-03 devnull .B
 69 058b0118 2005-01-03 devnull long	fsdirreadall(CFid *fid, Dir **d)
 70 058b0118 2005-01-03 devnull .PP
 71 058b0118 2005-01-03 devnull .B
 72 058b0118 2005-01-03 devnull Dir*	fsdirstat(CFsys *fs, char *path)
 73 058b0118 2005-01-03 devnull .PP
 74 058b0118 2005-01-03 devnull .B
 75 058b0118 2005-01-03 devnull Dir*	fsdirfstat(CFid *fid)
 76 058b0118 2005-01-03 devnull .PP
 77 058b0118 2005-01-03 devnull .B
 78 058b0118 2005-01-03 devnull int	fsdirwstat(CFsys *fs, char *path, Dir *d)
 79 058b0118 2005-01-03 devnull .PP
 80 058b0118 2005-01-03 devnull .B
 81 058b0118 2005-01-03 devnull int	fsdirfwstat(CFid *fid, Dir *d)
 82 058b0118 2005-01-03 devnull .PP
 83 058b0118 2005-01-03 devnull .B
 84 058b0118 2005-01-03 devnull int	fsopenfd(CFsys *fs, char *path, int mode)
 85 058b0118 2005-01-03 devnull .SH DESCRIPTION
 86 058b0118 2005-01-03 devnull The
 87 058b0118 2005-01-03 devnull .I 9pclient
 88 058b0118 2005-01-03 devnull library helps client programs interact with 9P servers.
 89 058b0118 2005-01-03 devnull .PP
 90 058b0118 2005-01-03 devnull A
 91 058b0118 2005-01-03 devnull .B CFsys*
 92 058b0118 2005-01-03 devnull represents a connection to a 9P server.
 93 058b0118 2005-01-03 devnull A
 94 058b0118 2005-01-03 devnull .B CFid*
 95 058b0118 2005-01-03 devnull represents an active fid on some connection;
 96 058b0118 2005-01-03 devnull see
 97 058b0118 2005-01-03 devnull .IR intro (9p).
 98 058b0118 2005-01-03 devnull .PP
 99 058b0118 2005-01-03 devnull A new connection to a 9P server is typically established by
100 058b0118 2005-01-03 devnull .I fsmount
101 058b0118 2005-01-03 devnull or
102 058b0118 2005-01-03 devnull .IR nsmount .
103 058b0118 2005-01-03 devnull .I Fsmount
104 058b0118 2005-01-03 devnull initializes a new 9P conversation on the open file descriptor
105 058b0118 2005-01-03 devnull .IR fd ;
106 058b0118 2005-01-03 devnull .I nsmount
107 058b0118 2005-01-03 devnull connects to a service named
108 058b0118 2005-01-03 devnull .I name
109 058b0118 2005-01-03 devnull in the current name space directory
110 058b0118 2005-01-03 devnull (see
111 058b0118 2005-01-03 devnull .IR intro (4)).
112 058b0118 2005-01-03 devnull Both attach to the root of the file system
113 058b0118 2005-01-03 devnull using the attach name
114 058b0118 2005-01-03 devnull .IR aname .
115 058b0118 2005-01-03 devnull .I Fsroot
116 058b0118 2005-01-03 devnull returns the
117 058b0118 2005-01-03 devnull .B CFid*
118 058b0118 2005-01-03 devnull corresponding to this root.
119 058b0118 2005-01-03 devnull .PP
120 058b0118 2005-01-03 devnull .IR Fsinit ,
121 058b0118 2005-01-03 devnull .IR fsversion ,
122 058b0118 2005-01-03 devnull .IR fsauth ,
123 058b0118 2005-01-03 devnull .IR fsattach ,
124 058b0118 2005-01-03 devnull and
125 058b0118 2005-01-03 devnull .I fssetroot
126 058b0118 2005-01-03 devnull provide more detailed control over the file system connection
127 058b0118 2005-01-03 devnull than
128 058b0118 2005-01-03 devnull .I fsmount
129 058b0118 2005-01-03 devnull and
130 058b0118 2005-01-03 devnull .IR nsmount .
131 058b0118 2005-01-03 devnull .I Fsinit
132 058b0118 2005-01-03 devnull allocates a new 
133 058b0118 2005-01-03 devnull .B CFsys*
134 058b0118 2005-01-03 devnull corresponding to a 9P conversation on the file descriptor
135 058b0118 2005-01-03 devnull .IR fd .
136 058b0118 2005-01-03 devnull .I Fsversion
137 058b0118 2005-01-03 devnull executes a 
138 058b0118 2005-01-03 devnull .IR version (9p)
139 058b0118 2005-01-03 devnull transaction to establish
140 058b0118 2005-01-03 devnull maximum message size and 9P version.
141 058b0118 2005-01-03 devnull .I Fsauth
142 058b0118 2005-01-03 devnull executes an
143 058b0118 2005-01-03 devnull .IR auth (9p)
144 058b0118 2005-01-03 devnull transaction, returning the new auth fid.
145 058b0118 2005-01-03 devnull .RI ( Fsread
146 058b0118 2005-01-03 devnull and
147 058b0118 2005-01-03 devnull .I fswrite
148 058b0118 2005-01-03 devnull can then be used to run the authentication protocol over the fid.)
149 058b0118 2005-01-03 devnull .I Fsattach
150 058b0118 2005-01-03 devnull executes an
151 058b0118 2005-01-03 devnull .IR attach (9p)
152 058b0118 2005-01-03 devnull transaction to connect to the root of a file tree served by the server.
153 058b0118 2005-01-03 devnull It presents
154 058b0118 2005-01-03 devnull .I afid
155 058b0118 2005-01-03 devnull (which may be nil)
156 058b0118 2005-01-03 devnull to establish identity.
157 058b0118 2005-01-03 devnull .I Fssetroot
158 058b0118 2005-01-03 devnull sets the root fid used by
159 058b0118 2005-01-03 devnull .IR fsopen ,
160 058b0118 2005-01-03 devnull .IR fsopenfd ,
161 058b0118 2005-01-03 devnull .IR fsdirstat ,
162 058b0118 2005-01-03 devnull and
163 058b0118 2005-01-03 devnull .IR fsdirwstat ,
164 058b0118 2005-01-03 devnull which evaluate rooted path names.
165 058b0118 2005-01-03 devnull .PP
166 058b0118 2005-01-03 devnull When a fid
167 058b0118 2005-01-03 devnull is no longer needed, it should be clunked by calling
168 058b0118 2005-01-03 devnull .I fsclose
169 058b0118 2005-01-03 devnull and then considered freed.
170 058b0118 2005-01-03 devnull Similarly, when the connection to the server is no longer needed,
171 058b0118 2005-01-03 devnull it should be closed by calling
172 058b0118 2005-01-03 devnull .IR fsunmount ,
173 058b0118 2005-01-03 devnull which will take care of calling
174 058b0118 2005-01-03 devnull .I fsclose
175 058b0118 2005-01-03 devnull on the current root fid.
176 058b0118 2005-01-03 devnull Once all fids have been clunked
177 058b0118 2005-01-03 devnull .I and
178 058b0118 2005-01-03 devnull the connection has been closed
179 058b0118 2005-01-03 devnull (the order is not important),
180 058b0118 2005-01-03 devnull the allocated structures will be freed and the
181 058b0118 2005-01-03 devnull file descriptor corresponding to the connection
182 058b0118 2005-01-03 devnull will be closed
183 058b0118 2005-01-03 devnull (see
184 058b0118 2005-01-03 devnull .IR close (2)).
185 058b0118 2005-01-03 devnull Fids are not reference counted: when
186 058b0118 2005-01-03 devnull .I fsclose
187 058b0118 2005-01-03 devnull is called, the clunk transaction and freeing of storage
188 058b0118 2005-01-03 devnull happen immediately.
189 058b0118 2005-01-03 devnull .PP
190 058b0118 2005-01-03 devnull .I Fscreate
191 058b0118 2005-01-03 devnull and
192 058b0118 2005-01-03 devnull .I fsopen
193 058b0118 2005-01-03 devnull establish new fids using the
194 058b0118 2005-01-03 devnull .IR walk ,
195 058b0118 2005-01-03 devnull .I create
196 058b0118 2005-01-03 devnull and
197 058b0118 2005-01-03 devnull .I open
198 058b0118 2005-01-03 devnull transactions
199 058b0118 2005-01-03 devnull (see
200 058b0118 2005-01-03 devnull .IR walk (9p)
201 058b0118 2005-01-03 devnull and
202 058b0118 2005-01-03 devnull .IR open (9p)).
203 058b0118 2005-01-03 devnull The
204 058b0118 2005-01-03 devnull .I path
205 058b0118 2005-01-03 devnull argument is evaluated relative to the
206 058b0118 2005-01-03 devnull .B CFsys
207 058b0118 2005-01-03 devnull root
208 058b0118 2005-01-03 devnull (see
209 058b0118 2005-01-03 devnull .I fsroot
210 058b0118 2005-01-03 devnull and
211 058b0118 2005-01-03 devnull .I fssetroot
212 058b0118 2005-01-03 devnull above).
213 058b0118 2005-01-03 devnull The path is parsed as a slash-separated sequence of path elements,
214 058b0118 2005-01-03 devnull as on Unix and Plan 9.
215 058b0118 2005-01-03 devnull Elements that are empty or
216 058b0118 2005-01-03 devnull dot
217 c8b6342d 2005-01-13 devnull .RB ( . )
218 058b0118 2005-01-03 devnull are ignored.
219 058b0118 2005-01-03 devnull .PP
220 058b0118 2005-01-03 devnull Once opened, these fids can be read and written using
221 058b0118 2005-01-03 devnull .I fspread
222 058b0118 2005-01-03 devnull and
223 058b0118 2005-01-03 devnull .IR fspwrite ,
224 058b0118 2005-01-03 devnull which execute
225 058b0118 2005-01-03 devnull .I read
226 058b0118 2005-01-03 devnull and
227 058b0118 2005-01-03 devnull .I write
228 058b0118 2005-01-03 devnull transactions
229 058b0118 2005-01-03 devnull (see
230 058b0118 2005-01-03 devnull .IR read (9p)).
231 058b0118 2005-01-03 devnull The library maintains an offset for each fid,
232 058b0118 2005-01-03 devnull analagous to the offset maintained by the kernel for each open file descriptor.
233 058b0118 2005-01-03 devnull .I Fsread
234 058b0118 2005-01-03 devnull and
235 058b0118 2005-01-03 devnull .I fswrite
236 058b0118 2005-01-03 devnull read and write from this offset, and update it after successful calls.
237 058b0118 2005-01-03 devnull Calling
238 058b0118 2005-01-03 devnull .I fspread
239 058b0118 2005-01-03 devnull or
240 058b0118 2005-01-03 devnull .I fspwrite
241 058b0118 2005-01-03 devnull with an
242 058b0118 2005-01-03 devnull .I offset
243 058b0118 2005-01-03 devnull of \-1
244 058b0118 2005-01-03 devnull is identical to calling
245 058b0118 2005-01-03 devnull .I fsread
246 058b0118 2005-01-03 devnull or
247 058b0118 2005-01-03 devnull .IR fswrite .
248 058b0118 2005-01-03 devnull .I Fsreadn
249 058b0118 2005-01-03 devnull calls
250 058b0118 2005-01-03 devnull .I fsread
251 058b0118 2005-01-03 devnull repeatedly to obtain exactly
252 058b0118 2005-01-03 devnull .I n
253 058b0118 2005-01-03 devnull bytes of data, unless it encounters end-of-file or an error.
254 058b0118 2005-01-03 devnull .PP
255 058b0118 2005-01-03 devnull Reading an open a directory returns directory entries encoded as described in
256 058b0118 2005-01-03 devnull .IR stat (9p).
257 058b0118 2005-01-03 devnull .I Fsdirread
258 058b0118 2005-01-03 devnull calls
259 058b0118 2005-01-03 devnull .I fsread
260 058b0118 2005-01-03 devnull and then parses the encoded entries into an array of
261 058b0118 2005-01-03 devnull .B Dir*
262 058b0118 2005-01-03 devnull data structures,
263 058b0118 2005-01-03 devnull storing a pointer to the array in
264 058b0118 2005-01-03 devnull .BI *d
265 058b0118 2005-01-03 devnull and returning the number of entries.
266 058b0118 2005-01-03 devnull .I Fsdirreadall
267 058b0118 2005-01-03 devnull is similar but reads the entire directory.
268 058b0118 2005-01-03 devnull The returned pointer should be freed with
269 058b0118 2005-01-03 devnull .I free
270 058b0118 2005-01-03 devnull (see
271 058b0118 2005-01-03 devnull .IR malloc (3))
272 058b0118 2005-01-03 devnull when no longer needed.
273 058b0118 2005-01-03 devnull .PP
274 058b0118 2005-01-03 devnull .I Fsdirfstat
275 058b0118 2005-01-03 devnull and
276 058b0118 2005-01-03 devnull .I fsdirfwstat
277 058b0118 2005-01-03 devnull execute
278 058b0118 2005-01-03 devnull .I stat
279 058b0118 2005-01-03 devnull and
280 058b0118 2005-01-03 devnull .I wstat
281 058b0118 2005-01-03 devnull (see
282 058b0118 2005-01-03 devnull .IR stat (9p))
283 058b0118 2005-01-03 devnull transactions.
284 058b0118 2005-01-03 devnull The
285 058b0118 2005-01-03 devnull .B Dir
286 058b0118 2005-01-03 devnull structure returned by 
287 058b0118 2005-01-03 devnull .I fsdirfstat
288 058b0118 2005-01-03 devnull should be freed with
289 058b0118 2005-01-03 devnull .I free
290 058b0118 2005-01-03 devnull (see
291 058b0118 2005-01-03 devnull .IR malloc (3))
292 058b0118 2005-01-03 devnull when no longer needed.
293 058b0118 2005-01-03 devnull .PP
294 058b0118 2005-01-03 devnull .I Fsdirstat
295 058b0118 2005-01-03 devnull and
296 058b0118 2005-01-03 devnull .I fsdirwstat
297 058b0118 2005-01-03 devnull are similar to
298 058b0118 2005-01-03 devnull .I fsdirfstat
299 058b0118 2005-01-03 devnull and
300 058b0118 2005-01-03 devnull .I fsdirfwstat
301 058b0118 2005-01-03 devnull but operate on paths relative to the file system root
302 058b0118 2005-01-03 devnull (see
303 058b0118 2005-01-03 devnull .I fsopen
304 058b0118 2005-01-03 devnull and
305 058b0118 2005-01-03 devnull .I fscreate
306 058b0118 2005-01-03 devnull above).
307 058b0118 2005-01-03 devnull .PP
308 058b0118 2005-01-03 devnull .I Fsopenfd
309 058b0118 2005-01-03 devnull opens a file on the 9P server
310 058b0118 2005-01-03 devnull for reading or writing but returns a Unix file descriptor
311 058b0118 2005-01-03 devnull instead of a fid structure.
312 058b0118 2005-01-03 devnull The file descriptor is actually one end of a
313 058b0118 2005-01-03 devnull .IR pipe (2).
314 058b0118 2005-01-03 devnull A proxy process on the other end is ferrying data
315 058b0118 2005-01-03 devnull between the pipe and the 9P fid.
316 058b0118 2005-01-03 devnull Because of the implementation as a pipe,
317 058b0118 2005-01-03 devnull the only signal of a read or write error is the closing of the pipe.
318 058b0118 2005-01-03 devnull The file descriptor remains valid even after the
319 058b0118 2005-01-03 devnull .B CFsys
320 058b0118 2005-01-03 devnull is unmounted.
321 058b0118 2005-01-03 devnull .SH SOURCE
322 c3674de4 2005-01-11 devnull .B \*9/src/lib9pclient
323 058b0118 2005-01-03 devnull .SH SEE ALSO
324 058b0118 2005-01-03 devnull .IR intro (4),
325 058b0118 2005-01-03 devnull .IR intro (9p)
326 058b0118 2005-01-03 devnull .SH BUGS
327 058b0118 2005-01-03 devnull The implementation
328 058b0118 2005-01-03 devnull should use a special version string to distinguish between
329 058b0118 2005-01-03 devnull servers that support
330 058b0118 2005-01-03 devnull .IR openfd (9p)
331 058b0118 2005-01-03 devnull and servers that do not.
332 058b0118 2005-01-03 devnull .PP
333 058b0118 2005-01-03 devnull The interface does not provide access to the
334 058b0118 2005-01-03 devnull .IR walk (9p)
335 058b0118 2005-01-03 devnull transaction, or to
336 058b0118 2005-01-03 devnull .I open
337 058b0118 2005-01-03 devnull and
338 058b0118 2005-01-03 devnull .I create
339 058b0118 2005-01-03 devnull on already-established fids.
340 058b0118 2005-01-03 devnull .PP
341 058b0118 2005-01-03 devnull There is no
342 058b0118 2005-01-03 devnull .IR fsseek .