ACME(4)                                                   ACME(4)

     NAME
          acme - control files for text windows

     SYNOPSIS
          acme [ -ab ] [ -c ncol ] [ -f varfont ] [ -F fixfont ] [ -l
          file | 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 vir-
          tual console; others control operations of acme itself.
          When a command is run under acme, a directory holding these
          files is mounted on /mnt/acme (also bound to /mnt/wsys) and
          also /dev; the files mentioned here appear in both those
          directories.

          Some of these files supply virtual versions of services
          available from the underlying environment, in particular the
          character terminal files cons(3). (Unlike in rio(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 running.  It has no specific function
               under acme itself.

          cons is the standard and diagnostic output file for all com-
               mands run under acme. (Input for commands is redirected
               to /dev/null.)  Text written to cons appears in a win-
               dow 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 compati-
               bility; there is no way to turn off `echo', for exam-
               ple, 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 char-
               acters (runes) in the tag; number of characters in the
               body; a 1 if the window is a directory, 0 otherwise;
               and a 1 if the window is modified, 0 otherwise-followed
               by the tag up to a newline if present.  Thus at charac-
               ter position 5×12 starts the name of the window.  If a

     ACME(4)                                                   ACME(4)

               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 compatibility with rio.

          new  A directory analogous to the numbered directories
               (q.v.).  Accessing any file in new creates a new win-
               dow.  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 discov-
          ered by the ID command, by reading the ctl file, or indi-
          rectly 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 com-
               pound 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, formatted as 2 decimal numbers m
               and n, each formatted in 11 characters plus a blank.  M
               and n are the character (not byte) offsets of the
               beginning and end of the address, which would be
               expressed in acme 's input language as #m,#n.  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 offset is ignored.

          ctl  may be read to recover the five numbers as held in the
               index file, described above, plus three more fields:
               the width of the window in pixels, the name of the font
               used in the window, and the width of a tab character in
               pixels.  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.
               dirty       Mark the window dirty, the opposite of
                           clean.

     ACME(4)                                                   ACME(4)

               cleartag    Remove all text in the tag after the verti-
                           cal bar.
               del         Equivalent to the Del interactive command.
               delete      Equivalent to the Delete interactive com-
                           mand.
               dot=addr    Set the user's selected text in the window
                           to the text addressed by the addr address.
               dump command
                           Set the command string to recreate the win-
                           dow from a dump file.
               dumpdir directory
                           Set the directory in which to run the com-
                           mand to recreate the window from a dump
                           file.
               get         Equivalent to the Get interactive command
                           with no arguments; accepts no arguments.
               limit=addr  When the ctl file is first opened, regular
                           expression context searches in addr
                           addresses examine the whole file; this mes-
                           sage 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 individually.
               menu        Maintain Undo, Redo, and Put in the left
                           half of the tag.  (This is the default for
                           file windows.)
               name name   Set the name of the window to name.
               nomark      Turn off automatic `marking' of changes, so
                           a set of related changes may be undone in a
                           single Undo interactive command.
               nomenu      Do not maintain Undo, Redo, and Put in the
                           left half of the tag.  (This is the default
                           for directory and error windows.)
               noscroll    Turn off automatic `scrolling' of the win-
                           dow to show text written to the body.
               put         Equivalent to the Put interactive command
                           with no arguments; accepts no arguments.
               scroll      Cancel a noscroll message, returning the
                           window to the default 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 contents of the body.  The file offset is ignored
               when writing the data file; instead the location of the
               data to be read or written is determined by the state
               of the addr file.  Text, which must contain only whole
               characters (no `partial runes'), written to data
               replaces the characters addressed by the addr file and

     ACME(4)                                                   ACME(4)

               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.

          errors
               Writing to the errors file appends to the body of the
               dir/+Errors window, where dir is the directory cur-
               rently named in the tag.  The window is created if nec-
               essary, but not until text is actually written.

          event
               When a window's event file is open, changes to the win-
               dow 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 program
               reading the event file will interpret them.  The mes-
               sages 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 new-
               line.  The first and second numbers are the character
               addresses of the action, the third is a flag, and the
               final 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 included 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 expansion; if so,
               another complete message will follow describing the
               expansion exactly as if it had been indicated

     ACME(4)                                                   ACME(4)

               explicitly (its flag will always be 0); 8 if the com-
               mand has an extra (chorded) argument; if so, two more
               complete messages will follow reporting the argument
               (with all numbers 0 except the character 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 follow-
               ing: 1 if acme can interpret the action without loading
               a new file; 2 if a second (post-expansion) message fol-
               lows, 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 omitted, 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.

          xdata
               The xdata file like data except that reads stop at the
               end address.

     SOURCE
          /sys/src/cmd/acme

     SEE ALSO
          rio(1), acme(1), cons(3).