3 acme \- control files for text windows
17 The text window system
19 serves a variety of files for reading, writing, and controlling
21 Some of them are virtual versions of system files for dealing
22 with the virtual console; others control operations
26 When a command is run under
28 a directory holding these files is posted as the 9P service
33 Some of these files supply virtual versions of services available from the underlying
34 environment, in particular the character terminal files in Plan 9's
36 (Unlike in Plan 9's \fIrio\fR(1),
39 sees the same set of files; there is not a distinct
42 Other files are unique to
46 is a subdirectory used by
50 as a mount point for the
52 files associated with the window in which
55 It has no specific function under
60 is the standard and diagnostic output file for all commands
63 (Input for commands is redirected to
67 appears in a window labeled
71 is the directory in which the command
73 The window is created if necessary, but not until text is actually written.
76 Is an empty unwritable file present only for compatibility; there is no way
77 to turn off `echo', for example, under
81 holds a sequence of lines of text, one per window. Each line has 5 decimal numbers,
82 each formatted in 11 characters plus a blank\(emthe window ID;
83 number of characters (runes) in the tag;
84 number of characters in the body;
85 a 1 if the window is a directory, 0 otherwise;
86 and a 1 if the window is modified, 0
87 otherwise\(emfollowed by the tag up to a newline if present.
88 Thus at character position 5×12 starts the name of the window.
89 If a file has multiple zeroxed windows open,
90 only the most recently used will appear in the
95 is an empty file, writable without effect, present only for compatibility with
99 A directory analogous to the numbered directories
104 creates a new window. Thus to cause text to appear in a new window,
107 For more control, open
109 and use the interface described below.
114 window has associated a directory numbered by its ID.
115 Window IDs are chosen sequentially and may be discovered by the
121 indirectly through the
123 file. The files in the numbered directories are as follows.
126 may be written with any textual address (line number, regular expression, etc.),
127 in the format understood by button 3 but without the initial colon, including compound addresses,
128 to set the address for text accessed through the
131 When read, it returns the value of the address that would next be read
132 or written through the
140 are character (not byte) offsets. If
144 are identical, the format is just
146 Thus a regular expression may be evaluated by writing it to
151 address has no effect on the user's selection of text.
154 holds contents of the window body. It may be read at any byte offset.
157 is always appended; the file offset is ignored.
160 may be read to recover the five numbers as held in the
162 file, described above, plus three more fields: the width of the
163 window in pixels, the name of the font used in the window,
164 and the width of a tab character in pixels.
165 Text messages may be written to
167 to affect the window.
168 Each message is terminated by a newline and multiple
169 messages may be sent in a single write.
176 address to that of the user's selected text in the window.
179 Mark the window clean as though it has just been written.
182 Mark the window dirty, the opposite of clean.
185 Remove all text in the tag after the vertical bar.
198 Set the user's selected text in the window to the text addressed by the
203 Set the command string to recreate the window from a dump file.
205 .BI dumpdir " directory
206 Set the directory in which to run the command to recreate the window from a dump file.
211 interactive command with no arguments; accepts no arguments.
216 file is first opened, regular expression context searches in
218 addresses examine the whole file; this message restricts subsequent
219 searches to the current
226 returning the window to the usual state wherein each modification to the
227 body must be undone individually.
230 Set the name of the window to
234 Turn off automatic `marking' of changes, so a set of related changes
235 may be undone in a single
240 Turn off automatic `scrolling' of the window to show text written to the body.
245 interactive command with no arguments; accepts no arguments.
250 message, returning the window to the default state wherein each write
253 file causes the window to `scroll' to display the new text.
256 Guarantee at least some of the selected text is visible on the display.
261 is used in conjunction with
263 for random access to the contents of the body.
264 The file offset is ignored when writing the
266 file; instead the location of the data to be read or written is determined by the state of the
269 Text, which must contain only whole characters (no `partial runes'),
272 replaces the characters addressed by the
274 file and sets the address to the null string at the end of the written text.
277 returns as many whole characters as the read count will permit starting
278 at the beginning of the
280 address (the end of the address has no effect)
281 and sets the address to the null string at the end of the returned
287 file appends to the body of the
291 is the directory currently named in the tag.
292 The window is created if necessary,
293 but not until text is actually written.
298 file is open, changes to the window occur as always but the
299 actions are also reported as
300 messages to the reader of the file. Also, user actions with buttons 2 and 3
305 which behave normally) have no immediate effect on the window;
306 it is expected that the program reading the
308 file will interpret them.
309 The messages have a fixed format:
310 a character indicating the origin or cause of the action,
311 a character indicating the type of the action,
312 four free-format blank-terminated decimal numbers,
313 optional text, and a newline.
314 The first and second numbers are the character addresses of the action,
316 and the final is a count of the characters in the optional text, which
317 may itself contain newlines.
318 The origin characters are
326 for actions through the window's other files,
328 for the keyboard, and
331 The type characters are
333 for text deleted from the body,
335 for text deleted from the tag,
337 for text inserted to the body,
339 for text inserted to the tag,
341 for a button 3 action in the body,
343 for a button 3 action in the tag,
345 for a button 2 action in the body, and
347 for a button 2 action in the tag.
349 If the relevant text has less than 256 characters, it is included in the message;
350 otherwise it is elided, the fourth number is 0, and the program must read
353 file if needed. No text is sent on a
365 the flag is always zero.
370 the flag is a bitwise OR (reported decimally) of the following:
371 1 if the text indicated is recognized as an
374 2 if the text indicated is a null string that has a non-null expansion;
375 if so, another complete message will follow describing the expansion
376 exactly as if it had been indicated explicitly (its flag will always be 0);
377 8 if the command has an extra (chorded) argument; if so,
378 two more complete messages will follow reporting the argument (with
379 all numbers 0 except the character count) and where it originated, in the form of
380 a fully-qualified button 3 style address.
386 the flag is the bitwise OR of the following:
389 can interpret the action without loading a new file;
390 2 if a second (post-expansion) message follows, analogous to that with
393 4 if the text is a file or window name (perhaps with address) rather than
396 For messages with the 1 bit on in the flag,
397 writing the message back to the
399 file, but with the flag, count, and text omitted,
400 will cause the action to be applied to the file exactly as it would
403 file had not been open.
406 holds contents of the window tag. It may be read at any byte offset.
409 is always appended; the file offset is ignored.
416 except that reads stop at the end address.
