term% cat index.txt ACME(4) Kernel Interfaces Manual ACME(4)
NAME
acme - control files for text windows
SYNOPSIS
acme [ -f varfont ] [ -F fixfont ] [ file ... ]
DESCRIPTION
The text window system acme(1) serves a variety of files for reading,
writing, and controlling windows. Some of them are virtual versions of
system files for dealing with the virtual console; others control oper‐
ations of acme itself. When a command is run under acme, a directory
holding these files is mounted on /mnt/acme (also bound to /mnt/8½)
and also /dev; the files mentioned here appear in both those directo‐
ries.
Some of these files supply virtual versions of services available from
the underlying environment, in particular the character terminal files
cons(3). (Unlike in 8½(1), each command under acme sees the same set
of files; there is not a distinct /dev/cons for each window.) Other
files are unique to acme.
acme is a subdirectory used by win (see acme(1)) as a mount point for
the acme files associated with the window in which win is run‐
ning. It has no specific function under acme itself.
cons is the standard and diagnostic output file for all commands run
under acme. (Input for commands is redirected to /dev/null.)
Text written to cons appears in a window labeled dir/+Errors,
where dir is the directory in which the command was run. The
window is created if necessary, but not until text is actually
written.
consctl
Is an empty unwritable file present only for compatibility;
there is no way to turn off ‘echo', for example, under acme.
index holds a sequence of lines of text, one per window. Each line
has 5 decimal numbers, each formatted in 11 characters plus a
blank—the window ID; number of characters (runes) in the tag;
number of characters in the body; a 1 if the window is a direc‐
tory, 0 otherwise; and a 1 if the window is modified, 0 other‐
wise—followed by the tag up to a newline if present. Thus at
character position 5Ã12 starts the name of the window. If a
file has multiple zeroxed windows open, only the most recently
used will appear in the index file.
label is an empty file, writable without effect, present only for com‐
patibility with 8½.
new A directory analogous to the numbered directories (q.v.). Ac‐
cessing any file in new creates a new window. Thus to cause
text to appear in a new window, write it to /dev/new/body. For
more control, open /dev/new/ctl and use the interface described
below.
Each acme window has associated a directory numbered by its ID. Window
IDs are chosen sequentially and may be discovered by the ID command, by
reading the ctl file, or indirectly through the index file. The files
in the numbered directories are as follows.
addr may be written with any textual address (line number, regular
expression, etc.), in the format understood by button 3 but
without the initial colon, including compound addresses, to set
the address for text accessed through the data file. When read,
it returns the value of the address that would next be read or
written through the data file, in the format #m,#n where m and n
are character (not byte) offsets. If m and n are identical, the
format is just #m. Thus a regular expression may be evaluated
by writing it to addr and reading it back. The addr address has
no effect on the user's selection of text.
body holds contents of the window body. It may be read at any byte
offset. Text written to body is always appended; the file off‐
set is ignored.
ctl may be read to recover the five numbers as held in the index
file, described above. Text messages may be written to ctl to
affect the window. Each message is terminated by a newline and
multiple messages may be sent in a single write.
addr=dot
Set the addr address to that of the user's selected text in
the window.
clean Mark the window clean as though it has just been written.
cleartag
Remove all text in the tag after the vertical bar.
del Equivalent to the Del interactive command.
delete Equivalent to the Delete interactive command.
dot=addr
Set the user's selected text in the window to the text ad‐
dressed by the addr address.
dump command
Set the command string to recreate the window from a dump
file.
dumpdir directory
Set the directory in which to run the command to recreate
the window from a dump file.
get Equivalent to the Get interactive command with no argu‐
ments; accepts no arguments.
limit=addr
When the ctl file is first opened, regular expression con‐
text searches in addr addresses examine the whole file;
this message restricts subsequent searches to the current
addr address.
mark Cancel nomark, returning the window to the usual state
wherein each modification to the body must be undone indi‐
vidually.
name name
Set the name of the window to name.
nomark Turn off automatic ‘marking' of changes, so a set of re‐
lated changes may be undone in a single Undo interactive
command.
noscroll
Turn off automatic ‘scrolling' of the window to show text
written to the body.
put Equivalent to the Put interactive command with no argu‐
ments; accepts no arguments.
scroll Cancel a noscroll message, returning the window to the de‐
fault state wherein each write to the body file causes the
window to ‘scroll' to display the new text.
show Guarantee at least some of the selected text is visible on
the display.
data is used in conjunction with addr for random access to the con‐
tents of the body. The file offset is ignored when writing the
body file, but the character (not byte) offset may be set with
addr and then read from the data file. Text, which must contain
only whole characters (no ‘partial runes'), written to data re‐
places the characters addressed by the addr file and sets the
address to the null string at the end of the written text. A
read from data returns as many whole characters as the read
count will permit starting at the beginning of the addr address
(the end of the address has no effect) and sets the address to
the null string at the end of the returned characters.
event When a window's event file is open, changes to the window occur
as always but the actions are also reported as messages to the
reader of the file. Also, user actions with buttons 2 and 3
(other than chorded Cut and Paste, which behave normally) have
no immediate effect on the window; it is expected that the pro‐
gram reading the event file will interpret them. The messages
have a fixed format: a character indicating the origin or cause
of the action, a character indicating the type of the action,
four free-format blank-terminated decimal numbers, optional
text, and a newline. The first and second numbers are the char‐
acter addresses of the action, the third is a flag, and the fi‐
nal is a count of the characters in the optional text, which may
itself contain newlines. The origin characters are E for writes
to the body or tag file, F for actions through the window's
other files, K for the keyboard, and M for the mouse. The type
characters are D for text deleted from the body, d for text
deleted from the tag, I for text inserted to the body, i for
text inserted to the tag, L for a button 3 action in the body, l
for a button 3 action in the tag, X for a button 2 action in the
body, and x for a button 2 action in the tag.
If the relevant text has less than 256 characters, it is in‐
cluded in the message; otherwise it is elided, the fourth number
is 0, and the program must read it from the data file if needed.
No text is sent on a D or d message.
For D, d, I, and i the flag is always zero. For X and x, the
flag is a bitwise OR (reported decimally) of the following: 1 if
the text indicated is recognized as an acme built-in command; 2
if the text indicated is a null string that has a non-null ex‐
pansion; if so, another complete message will follow describing
the expansion exactly as if it had been indicated explicitly
(its flag will always be 0); 8 if the command has an extra
(chorded) argument; if so, two more complete messages will fol‐
low reporting the argument (with all numbers 0 except the char‐
acter count) and where it originated, in the form of a fully-
qualified button 3 style address.
For L and l, the flag is the bitwise OR of the following: 1 if
acme can interpret the action without loading a new file; 2 if a
second (post-expansion) message follows, analogous to that with
X messages; 4 if the text is a file or window name (perhaps with
address) rather than plain literal text.
For messages with the 1 bit on in the flag, writing the message
back to the event file, but with the flag, count, and text omit‐
ted, will cause the action to be applied to the file exactly as
it would have been if the event file had not been open.
tag holds contents of the window tag. It may be read at any byte
offset. Text written to tag is always appended; the file offset
is ignored.
SOURCE
/sys/src/cmd/acme
SEE ALSO
8½(1), acme(1), cons(3).
ACME(4)