Provided by: libtickit-perl_0.73-1build3_amd64 
NAME
"Tickit::Term" - terminal formatting abstraction
SYNOPSIS
DESCRIPTION
Provides terminal control primitives for Tickit; a number of methods that control the terminal by writing
control strings. This object itself performs no actual IO work; it writes bytes to a delegated object
given to the constructor called the writer.
This object is not normally constructed directly by the containing application; instead it is used
indirectly by other parts of the "Tickit" distribution.
Note that a given program may contain multiple objects in this class that all refer to the same
underlying "TickitTerm" instance from the C library. This is especially true of the first argument
provided to event binding callbacks. This class overloads numify and stringify operations, so that
instances may be compared using the "==" or "eq" operators, or used as keys in hashes, and they will act
as expected. Do not rely on plain "refaddr" comparison however as you may get incorrect results.
CONSTRUCTOR
new
$term = Tickit::Term->new( %params )
Constructs a new "Tickit::Term" object.
Takes the following named arguments at construction time:
UTF8 => BOOL
If defined, overrides locale detection to enable or disable UTF-8 mode. If not defined then this
will be detected from the locale by using Perl's "${^UTF8LOCALE}" variable.
writer => OBJECT
An object delegated to for sending strings of terminal control bytes to the terminal itself. This
object must support a single method, "write", taking a string of bytes.
$writer->write( $data )
Such an interface is supported by an "IO::Handle" object.
output_handle => HANDLE
Optional. If supplied, will be used as the terminal filehandle for querying the size. Even if
supplied, all writing operations will use the "writer" function rather than performing IO
operations on this filehandle.
input_handle => HANDLE
Optional. If supplied, will be used as the terminal filehandle for reading keypress and other
events.
open_stdio
$term = Tickit::Term->open_stdio
Convenient shortcut for obtaining a Tickit::Term instance bound to the STDIN and STDOUT streams of the
process.
METHODS
get_input_handle
$fh = $term->get_input_handle
Returns the input handle set by the "input_handle" constructor arg.
Note that because Tickit::Term merely wraps an object provided by the lower-level libtickit C library, it
is no longer guaranteed that this method will return the same perl-level object that was given to the
constructor. The object may be newly-constructed to represent a new perl-level readable filehandle on the
same file number.
get_output_handle
$fh = $term->get_output_handle
Returns the output handle set by the "output_handle" constructor arg.
Note that because Tickit::Term merely wraps an object provided by the lower-level libtickit C library, it
is no longer guaranteed that this method will return the same perl-level object that was given to the
constructor. The object may be newly-constructed to represent a new perl-level writable filehandle on the
same file number.
set_output_buffer
$term->set_output_buffer( $len )
Sets the size of the output buffer
await_started
$term->await_started( $timeout )
Waits for the terminal startup process to complete, up to the timeout given in seconds.
pause
$term->pause
Suspends operation of the terminal by resetting it to its default state.
resume
$term->resume
Resumes operation of the terminal after a "pause".
Typically these two methods are used together, either side of a blocking wait around a "SIGSTOP".
sub suspend
{
$term->pause;
kill STOP => $$;
$term->resume;
$rootwin->expose;
}
teardown
$term->teardown
Shuts down operation of the terminal entirely, in preparation for terminating the process.
flush
$term->flush
Flushes the output buffer to the terminal
bind_event
$id = $term->bind_event( $ev, $code, $data )
Installs a new event handler to watch for the event specified by $ev, invoking the $code reference when
it occurs. $code will be invoked with the given terminal, the event name, an event information object,
and the $data value it was installed with. "bind_event" returns an ID value that may be used to remove
the handler by calling "unbind_event_id".
$ret = $code->( $term, $ev, $info, $data )
The type of $info will depend on the kind of event that was received, as indicated by $ev. The
information structure types are documented in Tickit::Event.
bind_event (with flags)
$id = $term->bind_event( $ev, $flags, $code, $data )
The $code argument may optionally be preceded by an integer of flag values. This should be zero to apply
default semantics, or a bitmask of one or more of the following constants:
TICKIT_BIND_FIRST
Inserts this event handler first in the chain, before any existing ones.
TICKIT_BIND_ONESHOT
Remove the event handler after it has been invoked the first time.
unbind_event_id
$term->unbind_event_id( $id )
Removes an event handler that returned the given $id value.
refresh_size
$term->refresh_size
If a filehandle was supplied to the constructor, fetch the size of the terminal and update the cached
sizes in the object. May invoke "on_resize" if the new size is different.
set_size
$term->set_size( $lines, $cols )
Defines the size of the terminal. Invoke "on_resize" if the new size is different.
lines
cols
$lines = $term->lines
$cols = $term->cols
Query the size of the terminal, as set by the most recent "refresh_size" or "set_size" operation.
goto
$success = $term->goto( $line, $col )
Move the cursor to the given position on the screen. If only one parameter is defined, does not alter the
other. Both $line and $col are 0-based.
Note that not all terminals can support these partial moves. This method returns a boolean indicating
success; if the terminal could not perform the move it will need to be retried using a fully-specified
call.
move
$term->move( $downward, $rightward )
Move the cursor relative to where it currently is.
scrollrect
$success = $term->scrollrect( $top, $left, $lines, $cols, $downward, $rightward )
Attempt to scroll the rectangle of the screen defined by the first four parameters by an amount given by
the latter two. Since most terminals cannot perform arbitrary rectangle scrolling, this method returns a
boolean to indicate if it was successful. The caller should test this return value and fall back to
another drawing strategy if the attempt was unsuccessful.
The cursor may move as a result of calling this method; its location is undefined if this method returns
successful.
chpen
$term->chpen( $pen )
$term->chpen( %attrs )
Changes the current pen attributes to those given. Any attribute whose value is given as "undef" is
reset. Any attributes not named are unchanged.
For details of the supported pen attributes, see Tickit::Pen.
setpen
$term->setpen( $pen )
$term->setpen( %attrs )
Similar to "chpen", but completely defines the state of the terminal pen. Any attribute not given will be
reset to its default value.
print
$term->print( $text, [ $pen ] )
Print the given text to the terminal at the current cursor position.
An optional "Tickit::Pen" may be provided; if present it will be set as if given to "setpen" first.
clear
$term->clear( [ $pen ] )
Erase the entire screen.
An optional "Tickit::Pen" may be provided; if present it will be set as if given to "setpen" first.
erasech
$term->erasech( $count, $moveend, [ $pen ] )
Erase $count characters forwards. If $moveend is true, the cursor is moved to the end of the erased
region. If defined but false, the cursor will remain where it is. If undefined, the terminal will perform
whichever of these behaviours is more efficient, and the cursor will end at some undefined location.
Using $moveend may be more efficient than separate "erasech" and "goto" calls on terminals that do not
have an erase function, as it will be implemented by printing spaces. This removes the need for two
cursor jumps.
An optional "Tickit::Pen" may be provided; if present it will be set as if given to "setpen" first.
getctl_int
setctl_int
$value = $term->getctl_int( $ctl )
$success = $term->setctl_int( $ctl, $value )
Gets or sets the value of an integer terminal control option. $ctl should be one of the following
options. They can be specified either as integers, using the following named constants, or as strings
giving the part following "TERMCTL_" in lower-case.
On failure, each method returns "undef".
TERMCTL_ALTSCREEN
Enables DEC Alternate Screen mode
TERMCTL_CURSORVIS
Enables cursor visible mode
TERMCTL_CURSORBLINK
Enables cursor blinking mode
TERMCTL_CURSORSHAPE
Sets the shape of the cursor. $value should be one of "CURSORSHAPE_BLOCK", "CURSORSHAPE_UNDER" or
"CURSORSHAPE_LEFT_BAR".
TERMCTL_KEYPAD_APP
Enables keypad application mode
TERMCTL_MOUSE
Enables mouse tracking mode. $vaule should be one of "TERM_MOUSEMODE_CLICK",
"TERM_MOUSEMODE_DRAG", "TERM_MOUSEMODE_MOVE" or "TERM_MOUSEMODE_OFF".
setctl_str
$success = $term->setctl_str( $ctl, $value )
Sets the value of a string terminal control option. $ctrl should be one of the following options. They
can be specified either as integers or strings, as for "setctl_int".
TERMCTL_ICON_TEXT
TERMCTL_TITLE_TEXT
TERMCTL_ICONTITLE_TEXT
Sets the terminal window icon text, title, or both.
getctl
setctl
$value = $term->getctl( $ctl )
$success = $term->setctl( $ctl, $value )
A newer form of the various typed get and set methods above. This version will interpret the given value
as appropriate, depending on the control type.
input_push_bytes
$term->input_push_bytes( $bytes )
Feeds more bytes of input. May result in "key" or "mouse" events.
input_readable
$term->input_readable
Informs the term that the input handle may be readable. Attempts to read more bytes of input. May result
in "key" or "mouse" events.
input_wait
$term->input_wait( $timeout )
Block until some input is available, and process it. Returns after one round of input has been processed.
May result in "key" or "mouse" events. If $timeout is defined, it will wait a period of time no longer
than this time before returning, even if no input events were received.
check_timeout
$timeout = $term->check_timeout
Returns a number in seconds to represent when the next timeout should occur on the terminal, or "undef"
if nothing is waiting. May invoke expired timeouts, and cause a "key" event to occur.
emit_key
$term->emit_key(
type => $type, str => $str, [ mod => $mod ]
)
Invokes the key event handlers as if an event with the given info had just been received. The "mod"
argument is optional, a default of 0 will apply if it is missing.
emit_mouse
$term->emit_mouse(
type => $type, button => $button, line => $line, col => $col,
[ mod => $mod ]
)
Invokes the mouse event handlers as if an event with the given info had just been received. The "mod"
argument is optional, a default of 0 will apply if it is missing.
EVENTS
The following event types are emitted and may be observed by "bind_event".
resize
Emitted when the terminal itself has been resized.
key
Emitted when a key on the keyboard is pressed.
mouse
Emitted when a mouse button is pressed or released, the cursor moved while a button is held (a dragging
event), or the wheel is scrolled.
Behaviour of events involving more than one mouse button is not well-specified by terminals.
TODO
• Track cursor position, and optimise (or eliminate entirely) "goto" calls.
AUTHOR
Paul Evans <leonerd@leonerd.org.uk>