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 two more fields: the width of the
163 window in pixels and the name of the font used in the window.
164 Text messages may be written to
166 to affect the window.
167 Each message is terminated by a newline and multiple
168 messages may be sent in a single write.
175 address to that of the user's selected text in the window.
178 Mark the window clean as though it has just been written.
181 Mark the window dirty, the opposite of clean.
184 Remove all text in the tag after the vertical bar.
197 Set the user's selected text in the window to the text addressed by the
202 Set the command string to recreate the window from a dump file.
204 .BI dumpdir " directory
205 Set the directory in which to run the command to recreate the window from a dump file.
210 interactive command with no arguments; accepts no arguments.
215 file is first opened, regular expression context searches in
217 addresses examine the whole file; this message restricts subsequent
218 searches to the current
225 returning the window to the usual state wherein each modification to the
226 body must be undone individually.
229 Set the name of the window to
233 Turn off automatic `marking' of changes, so a set of related changes
234 may be undone in a single
239 Turn off automatic `scrolling' of the window to show text written to the body.
244 interactive command with no arguments; accepts no arguments.
249 message, returning the window to the default state wherein each write
252 file causes the window to `scroll' to display the new text.
255 Guarantee at least some of the selected text is visible on the display.
260 is used in conjunction with
262 for random access to the contents of the body.
263 The file offset is ignored when writing the
265 file; instead the location of the data to be read or written is determined by the state of the
268 Text, which must contain only whole characters (no `partial runes'),
271 replaces the characters addressed by the
273 file and sets the address to the null string at the end of the written text.
276 returns as many whole characters as the read count will permit starting
277 at the beginning of the
279 address (the end of the address has no effect)
280 and sets the address to the null string at the end of the returned
286 file appends to the body of the
290 is the directory currently named in the tag.
291 The window is created if necessary,
292 but not until text is actually written.
297 file is open, changes to the window occur as always but the
298 actions are also reported as
299 messages to the reader of the file. Also, user actions with buttons 2 and 3
304 which behave normally) have no immediate effect on the window;
305 it is expected that the program reading the
307 file will interpret them.
308 The messages have a fixed format:
309 a character indicating the origin or cause of the action,
310 a character indicating the type of the action,
311 four free-format blank-terminated decimal numbers,
312 optional text, and a newline.
313 The first and second numbers are the character addresses of the action,
315 and the final is a count of the characters in the optional text, which
316 may itself contain newlines.
317 The origin characters are
325 for actions through the window's other files,
327 for the keyboard, and
330 The type characters are
332 for text deleted from the body,
334 for text deleted from the tag,
336 for text inserted to the body,
338 for text inserted to the tag,
340 for a button 3 action in the body,
342 for a button 3 action in the tag,
344 for a button 2 action in the body, and
346 for a button 2 action in the tag.
348 If the relevant text has less than 256 characters, it is included in the message;
349 otherwise it is elided, the fourth number is 0, and the program must read
352 file if needed. No text is sent on a
364 the flag is always zero.
369 the flag is a bitwise OR (reported decimally) of the following:
370 1 if the text indicated is recognized as an
373 2 if the text indicated is a null string that has a non-null expansion;
374 if so, another complete message will follow describing the expansion
375 exactly as if it had been indicated explicitly (its flag will always be 0);
376 8 if the command has an extra (chorded) argument; if so,
377 two more complete messages will follow reporting the argument (with
378 all numbers 0 except the character count) and where it originated, in the form of
379 a fully-qualified button 3 style address.
385 the flag is the bitwise OR of the following:
388 can interpret the action without loading a new file;
389 2 if a second (post-expansion) message follows, analogous to that with
392 4 if the text is a file or window name (perhaps with address) rather than
395 For messages with the 1 bit on in the flag,
396 writing the message back to the
398 file, but with the flag, count, and text omitted,
399 will cause the action to be applied to the file exactly as it would
402 file had not been open.
405 holds contents of the window tag. It may be read at any byte offset.
408 is always appended; the file offset is ignored.
415 except that reads stop at the end address.
