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 reports a log of window operations since the opening of the
102 Each line describes a single operation using three fields separated by single spaces:
103 the decimal window ID, the operation, and the window name.
106 blocks until there is an operation to report, so reading the file
107 can be used to monitor editor activity and react to changes.
108 The reported operations are
112 (window creation via zerox),
118 The window name can be the empty string; in particular it is empty in
120 log entries corresponding to windows created by external programs.
123 is a directory analogous to the numbered directories
128 creates a new window. Thus to cause text to appear in a new window,
131 For more control, open
133 and use the interface described below.
138 window has associated a directory numbered by its ID.
139 Window IDs are chosen sequentially and may be discovered by the
145 indirectly through the
147 file. The files in the numbered directories are as follows.
150 may be written with any textual address (line number, regular expression, etc.),
151 in the format understood by button 3 but without the initial colon, including compound addresses,
152 to set the address for text accessed through the
155 When read, it returns the value of the address that would next be read
156 or written through the
164 are character (not byte) offsets. If
168 are identical, the format is just
170 Thus a regular expression may be evaluated by writing it to
175 address has no effect on the user's selection of text.
178 holds contents of the window body. It may be read at any byte offset.
181 is always appended; the file offset is ignored.
184 may be read to recover the five numbers as held in the
186 file, described above, plus three more fields: the width of the
187 window in pixels, the name of the font used in the window,
188 and the width of a tab character in pixels.
189 Text messages may be written to
191 to affect the window.
192 Each message is terminated by a newline and multiple
193 messages may be sent in a single write.
200 address to that of the user's selected text in the window.
203 Mark the window clean as though it has just been written.
206 Mark the window dirty, the opposite of clean.
209 Remove all text in the tag after the vertical bar.
222 Set the user's selected text in the window to the text addressed by the
227 Set the command string to recreate the window from a dump file.
229 .BI dumpdir " directory
230 Set the directory in which to run the command to recreate the window from a dump file.
235 interactive command with no arguments; accepts no arguments.
240 file is first opened, regular expression context searches in
242 addresses examine the whole file; this message restricts subsequent
243 searches to the current
250 returning the window to the usual state wherein each modification to the
251 body must be undone individually.
254 Set the name of the window to
258 Turn off automatic `marking' of changes, so a set of related changes
259 may be undone in a single
266 interactive command with no arguments; accepts no arguments.
269 Guarantee at least some of the selected text is visible on the display.
274 is used in conjunction with
276 for random access to the contents of the body.
277 The file offset is ignored when writing the
279 file; instead the location of the data to be read or written is determined by the state of the
282 Text, which must contain only whole characters (no `partial runes'),
285 replaces the characters addressed by the
287 file and sets the address to the null string at the end of the written text.
290 returns as many whole characters as the read count will permit starting
291 at the beginning of the
293 address (the end of the address has no effect)
294 and sets the address to the null string at the end of the returned
300 file appends to the body of the
304 is the directory currently named in the tag.
305 The window is created if necessary,
306 but not until text is actually written.
311 file is open, changes to the window occur as always but the
312 actions are also reported as
313 messages to the reader of the file. Also, user actions with buttons 2 and 3
318 which behave normally) have no immediate effect on the window;
319 it is expected that the program reading the
321 file will interpret them.
322 The messages have a fixed format:
323 a character indicating the origin or cause of the action,
324 a character indicating the type of the action,
325 four free-format blank-terminated decimal numbers,
326 optional text, and a newline.
327 The first and second numbers are the character addresses of the action,
329 and the final is a count of the characters in the optional text, which
330 may itself contain newlines.
331 The origin characters are
339 for actions through the window's other files,
341 for the keyboard, and
344 The type characters are
346 for text deleted from the body,
348 for text deleted from the tag,
350 for text inserted to the body,
352 for text inserted to the tag,
354 for a button 3 action in the body,
356 for a button 3 action in the tag,
358 for a button 2 action in the body, and
360 for a button 2 action in the tag.
362 If the relevant text has less than 256 characters, it is included in the message;
363 otherwise it is elided, the fourth number is 0, and the program must read
366 file if needed. No text is sent on a
378 the flag is always zero.
383 the flag is a bitwise OR (reported decimally) of the following:
384 1 if the text indicated is recognized as an
387 2 if the text indicated is a null string that has a non-null expansion;
388 if so, another complete message will follow describing the expansion
389 exactly as if it had been indicated explicitly (its flag will always be 0);
390 8 if the command has an extra (chorded) argument; if so,
391 two more complete messages will follow reporting the argument (with
392 all numbers 0 except the character count) and where it originated, in the form of
393 a fully-qualified button 3 style address.
399 the flag is the bitwise OR of the following:
402 can interpret the action without loading a new file;
403 2 if a second (post-expansion) message follows, analogous to that with
406 4 if the text is a file or window name (perhaps with address) rather than
409 For messages with the 1 bit on in the flag,
410 writing the message back to the
412 file, but with the flag, count, and text omitted,
413 will cause the action to be applied to the file exactly as it would
416 file had not been open.
419 holds contents of the window tag. It may be read at any byte offset.
422 is always appended; the file offset is ignored.
429 except that reads stop at the end address.