The window system
8½
serves a variety of files for reading, writing, and controlling
windows.
Some of them are virtual versions of system files for dealing
with the display, keyboard, and mouse; others control operations
of the window system itself.
8½
posts its service in the
/srv
directory, using a
name constructed from a catenation of the user ID
and a process id; the environment variable
$8½srv
is set to this service name within processes running under the control
of each invocation of
8½.
A
mount
(see
bind(1))
of that file causes
8½
to create a new window; the attach specifier in the
mount
gives the coordinates of the created window.
The syntax of the specifier is
Npid minx miny maxx maxy
where
pid
is the process id of a process in the note group
(see
fork(2))
to receive
interrupt
and
hangup
notes in that window.
The list of coordinates may be separated by blanks or commas.
When a window is created either by
the
window
command
(see
8½(1))
or by using the menu supplied by
8½,
this server is mounted on
/mnt/8½
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),
and all the bit devices
bit(3),
each specific to the window.
Other files are unique to
8½.
bitblt
is a virtual version of the
bitblt
file within the current window;
see
bit(3),
graphics(2).
All operations are clipped to the current window.
The coordinate system is absolute; it refers to the real screen.
cons
is a virtual version of the standard terminal file
cons(3).
8½
supplies extra editing features and a scroll bar
(see
8½(1)).
consctl
controls interpretation of keyboard input.
Writing strings on it sets these modes:
rawon
turns on raw mode;
rawoff
turns off raw mode;
holdon
turns on hold mode;
holdoff
turns off hold mode.
Closing the file makes the window revert to default state
(raw off, hold off).
kbd
This file intercepts the path between the keyboard and
cons.
Reading from it gathers characters typed towards the associated
window; writing to it inserts characters into the input stream
of that window.
label
initially contains a string with the process ID of the lead process
in the window and the command being executed there.
It may be written and is used as a tag when the window is hidden.
mouse
is a virtual version of the standard mouse file (see
bit(3)).
Opening it turns off scrolling, editing, and
8½-supplied
menus in the associated
window.
The 0x80 bit in the buttons byte of a returned record indicates that
the window has been reshaped.
Reading this file blocks until the mouse moves or a button changes.
Mouse movements or button changes are invisible when the mouse cursor
is located outside the window.
nbmouse
is a non-blocking version of
mouse;
it always returns the current state.
Its use is discouraged.
select
returns the selected text in the designated window.
It may not be written.
snarf
returns the string currently in the snarf buffer.
Writing this file sets the contents of the snarf buffer.
text
returns the full contents of the window.
It may not be written.
winid
returns the unique and unchangeable ID for the window;
it is a string of digits.
window
is the virtual version of
/dev/screen;
see
bit(3).
It contains the depth, coordinates, and bitmap corresponding to the associated
window.
windows
is a directory containing a subdirectory for each window, named
by the unique ID for that window. Within each subdirectory
are entries corresponding to several of the special files associated
with that window:
bitblt,
cons,
consctl,
label,
etc.
EXAMPLES
Cause a window to be created in the upper left corner,
and the word
hi
to be printed there.
mount $8½srv /tmp N$pid' 0 0 128 64'
echo hi > /tmp/cons