The module curses defines the following exception:
exceptionerror
Exception raised when a curses library function returns an error.
Note:
Whenever x or y arguments to a function
or a method are optional, they default to the current cursor location.
Whenever attr is optional, it defaults to A_NORMAL.
The module curses defines the following functions:
baudrate(
)
Returns the output speed of the terminal in bits per second. On
software terminal emulators it will have a fixed high value.
Included for historical reasons; in former times, it was used to
write output loops for time delays and occasionally to change
interfaces depending on the line speed.
beep(
)
Emit a short attention sound.
can_change_color(
)
Returns true or false, depending on whether the programmer can change
the colors displayed by the terminal.
cbreak(
)
Enter cbreak mode. In cbreak mode (sometimes called ``rare'' mode)
normal tty line buffering is turned off and characters are available
to be read one by one. However, unlike raw mode, special characters
(interrupt, quit, suspend, and flow control) retain their effects on
the tty driver and calling program. Calling first raw()
then cbreak() leaves the terminal in cbreak mode.
color_content(
color_number)
Returns the intensity of the red, green, and blue (RGB) components in
the color color_number, which must be between 0 and
COLORS. A 3-tuple is returned, containing the R,G,B values
for the given color, which will be between 0 (no component) and
1000 (maximum amount of component).
color_pair(
color_number)
Returns the attribute value for displaying text in the specified
color. This attribute value can be combined with
A_STANDOUT, A_REVERSE, and the other
A_* attributes. pair_number() is the
counterpart to this function.
curs_set(
visibility)
Sets the cursor state. visibility can be set to 0, 1, or 2, for
invisible, normal, or very visible. If the terminal supports the
visibility requested, the previous cursor state is returned;
otherwise, an exception is raised. On many terminals, the ``visible''
mode is an underline cursor and the ``very visible'' mode is a block cursor.
def_prog_mode(
)
Saves the current terminal mode as the ``program'' mode, the mode when
the running program is using curses. (Its counterpart is the
``shell'' mode, for when the program is not in curses.) Subsequent calls
to reset_prog_mode() will restore this mode.
def_shell_mode(
)
Saves the current terminal mode as the ``shell'' mode, the mode when
the running program is not using curses. (Its counterpart is the
``program'' mode, when the program is using curses capabilities.)
Subsequent calls
to reset_shell_mode() will restore this mode.
delay_output(
ms)
Inserts an ms millisecond pause in output.
doupdate(
)
Update the physical screen. The curses library keeps two data
structures, one representing the current physical screen contents
and a virtual screen representing the desired next state. The
doupdate() ground updates the physical screen to match the
virtual screen.
The virtual screen may be updated by a noutrefresh() call
after write operations such as addstr() have been performed
on a window. The normal refresh() call is simply
noutrefresh() followed by doupdate(); if you have
to update multiple windows, you can speed performance and perhaps
reduce screen flicker by issuing noutrefresh() calls on
all windows, followed by a single doupdate().
echo(
)
Enter echo mode. In echo mode, each character input is echoed to the
screen as it is entered.
endwin(
)
De-initialize the library, and return terminal to normal status.
erasechar(
)
Returns the user's current erase character. Under Unix operating
systems this is a property of the controlling tty of the curses
program, and is not set by the curses library itself.
filter(
)
The filter() routine, if used, must be called before
initscr() is called. The effect is that, during those
calls, LINES is set to 1; the capabilities clear, cup, cud, cud1,
cuu1, cuu, vpa are disabled; and the home string is set to the value of cr.
The effect is that the cursor is confined to the current line, and so
are screen updates. This may be used for enabling character-at-a-time
line editing without touching the rest of the screen.
flash(
)
Flash the screen. That is, change it to reverse-video and then change
it back in a short interval. Some people prefer such as `visible bell'
to the audible attention signal produced by beep().
flushinp(
)
Flush all input buffers. This throws away any typeahead that has
been typed by the user and has not yet been processed by the program.
getmouse(
)
After getch() returns KEY_MOUSE to signal a mouse
event, this method should be call to retrieve the queued mouse event,
represented as a 5-tuple
(id, x, y, z, bstate).
id is an ID value used to distinguish multiple devices,
and x, y, z are the event's coordinates. (z
is currently unused.). bstate is an integer value whose bits
will be set to indicate the type of event, and will be the bitwise OR
of one or more of the following constants, where n is the button
number from 1 to 4:
BUTTONn_PRESSED,
BUTTONn_RELEASED,
BUTTONn_CLICKED,
BUTTONn_DOUBLE_CLICKED,
BUTTONn_TRIPLE_CLICKED,
BUTTON_SHIFT,
BUTTON_CTRL,
BUTTON_ALT.
getsyx(
)
Returns the current coordinates of the virtual screen cursor in y and
x. If leaveok is currently true, then -1,-1 is returned.
getwin(
file)
Reads window related data stored in the file by an earlier
putwin() call. The routine then creates and initializes a
new window using that data, returning the new window object.
has_colors(
)
Returns true if the terminal can display colors; otherwise, it
returns false.
has_ic(
)
Returns true if the terminal has insert- and delete- character
capabilities. This function is included for historical reasons only,
as all modern software terminal emulators have such capabilities.
has_il(
)
Returns true if the terminal has insert- and
delete-line capabilities, or can simulate them using
scrolling regions. This function is included for historical reasons only,
as all modern software terminal emulators have such capabilities.
has_key(
ch)
Takes a key value ch, and returns true if the current terminal
type recognizes a key with that value.
halfdelay(
tenths)
Used for half-delay mode, which is similar to cbreak mode in that
characters typed by the user are immediately available to the program.
However, after blocking for tenths tenths of seconds, an
exception is raised if nothing has been typed. The value of
tenths must be a number between 1 and 255. Use
nocbreak() to leave half-delay mode.
init_color(
color_number, r, g, b)
Changes the definition of a color, taking the number of the color to
be changed followed by three RGB values (for the amounts of red,
green, and blue components). The value of color_number must be
between 0 and COLORS. Each of r, g,
b, must be a value between 0 and 1000. When
init_color() is used, all occurrences of that color on the
screen immediately change to the new definition. This function is a
no-op on most terminals; it is active only if
can_change_color() returns 1.
init_pair(
pair_number, fg, bg)
Changes the definition of a color-pair. It takes three arguments: the
number of the color-pair to be changed, the foreground color number,
and the background color number. The value of pair_number must
be between 1 and COLOR_PAIRS - 1 (the 0 color
pair is wired to white on black and cannot be changed). The value of
fg and bg arguments must be between 0 and
COLORS. If the color-pair was previously initialized, the
screen is refreshed and all occurrences of that color-pair are changed
to the new definition.
initscr(
)
Initialize the library. Returns a WindowObject which represents
the whole screen. Note:
If there is an error opening the terminal,
the underlying curses library may cause the interpreter to exit.
isendwin(
)
Returns true if endwin() has been called (that is, the
curses library has been deinitialized).
keyname(
k)
Return the name of the key numbered k. The name of a key
generating printable ASCII character is the key's character. The name
of a control-key combination is a two-character string consisting of a
caret followed by the corresponding printable ASCII character. The
name of an alt-key combination (128-255) is a string consisting of the
prefix `M-' followed by the name of the corresponding ASCII character.
killchar(
)
Returns the user's current line kill character. Under Unix operating
systems this is a property of the controlling tty of the curses
program, and is not set by the curses library itself.
longname(
)
Returns a string containing the terminfo long name field describing the current
terminal. The maximum length of a verbose description is 128
characters. It is defined only after the call to
initscr().
meta(
yes)
If yes is 1, allow 8-bit characters to be input. If yes is 0,
allow only 7-bit chars.
mouseinterval(
interval)
Sets the maximum time in milliseconds that can elapse between press and
release events in order for them to be recognized as a click, and
returns the previous interval value. The default value is 200 msec,
or one fifth of a second.
mousemask(
mousemask)
Sets the mouse events to be reported, and returns a tuple
(availmask, oldmask).
availmask indicates which of the
specified mouse events can be reported; on complete failure it returns
0. oldmask is the previous value of the given window's mouse
event mask. If this function is never called, no mouse events are
ever reported.
napms(
ms)
Sleep for ms milliseconds.
newpad(
nlines, ncols)
Creates and returns a pointer to a new pad data structure with the
given number of lines and columns. A pad is returned as a
window object.
A pad is like a window, except that it is not restricted by the screen
size, and is not necessarily associated with a particular part of the
screen. Pads can be used when a large window is needed, and only a
part of the window will be on the screen at one time. Automatic
refreshes of pads (such as from scrolling or echoing of input) do not
occur. The refresh() and noutrefresh() methods of a
pad require 6 arguments to specify the part of the pad to be
displayed and the location on the screen to be used for the display.
The arguments are pminrow, pmincol, sminrow, smincol, smaxrow,
smaxcol; the p arguments refer to the upper left corner of the pad
region to be displayed and the s arguments define a clipping box on
the screen within which the pad region is to be displayed.
newwin(
[nlines, ncols,] begin_y, begin_x)
Return a new window, whose left-upper corner is at
(begin_y, begin_x), and whose height/width is
nlines/ncols.
By default, the window will extend from the
specified position to the lower right corner of the screen.
nl(
)
Enter newline mode. This mode translates the return key into newline
on input, and translates newline into return and line-feed on output.
Newline mode is initially on.
nocbreak(
)
Leave cbreak mode. Return to normal ``cooked'' mode with line buffering.
noecho(
)
Leave echo mode. Echoing of input characters is turned off.
nonl(
)
Leave newline mode. Disable translation of return into newline on
input, and disable low-level translation of newline into
newline/return on output (but this does not change the behavior of
addch('\n'), which always does the equivalent of return and
line feed on the virtual screen). With translation off, curses can
sometimes speed up vertical motion a little; also, it will be able to
detect the return key on input.
noqiflush(
)
When the noqiflush routine is used, normal flush of input and
output queues associated with the INTR, QUIT and SUSP
characters will not be done. You may want to call
noqiflush() in a signal handler if you want output
to continue as though the interrupt had not occurred, after the
handler exits.
noraw(
)
Leave raw mode. Return to normal ``cooked'' mode with line buffering.
pair_content(
pair_number)
Returns a tuple (fg, bg) containing the colors for
the requested color pair. The value of pair_number must be
between 1 and COLOR_PAIRS - 1.
pair_number(
attr)
Returns the number of the color-pair set by the attribute value
attr. color_pair() is the counterpart to this
function.
putp(
string)
Equivalent to tputs(str, 1, putchar); emits the value of a
specified terminfo capability for the current terminal. Note that the
output of putp always goes to standard output.
qiflush(
[flag])
If flag is false, the effect is the same as calling
noqiflush(). If flag is true, or no argument is
provided, the queues will be flushed when these control characters are
read.
raw(
)
Enter raw mode. In raw mode, normal line buffering and
processing of interrupt, quit, suspend, and flow control keys are
turned off; characters are presented to curses input functions one
by one.
reset_prog_mode(
)
Restores the terminal to ``program'' mode, as previously saved
by def_prog_mode().
reset_shell_mode(
)
Restores the terminal to ``shell'' mode, as previously saved
by def_shell_mode().
setsyx(
y, x)
Sets the virtual screen cursor to y, x.
If y and x are both -1, then leaveok is set.
setupterm(
[termstr, fd])
Initializes the terminal. termstr is a string giving the
terminal name; if omitted, the value of the TERM environment variable
will be used. fd is the file descriptor to which any
initialization sequences will be sent; if not supplied, the file
descriptor for sys.stdout will be used.
start_color(
)
Must be called if the programmer wants to use colors, and before any
other color manipulation routine is called. It is good
practice to call this routine right after initscr().
start_color() initializes eight basic colors (black, red,
green, yellow, blue, magenta, cyan, and white), and two global
variables in the curses module, COLORS and
COLOR_PAIRS, containing the maximum number of colors and
color-pairs the terminal can support. It also restores the colors on
the terminal to the values they had when the terminal was just turned
on.
termattrs(
)
Returns a logical OR of all video attributes supported by the
terminal. This information is useful when a curses program needs
complete control over the appearance of the screen.
termname(
)
Returns the value of the environment variable TERM, truncated to 14
characters.
tigetflag(
capname)
Returns the value of the Boolean capability corresponding to the
terminfo capability name capname. The value -1 is
returned if capname is not a Boolean capability, or 0 if
it is canceled or absent from the terminal description.
tigetnum(
capname)
Returns the value of the numeric capability corresponding to the
terminfo capability name capname. The value -2 is
returned if capname is not a numeric capability, or -1 if
it is canceled or absent from the terminal description.
tigetstr(
capname)
Returns the value of the string capability corresponding to the
terminfo capability name capname. None is returned if
capname is not a string capability, or is canceled or absent
from the terminal description.
tparm(
str[,...])
Instantiates the string str with the supplied parameters, where
str should be a parameterized string obtained from the terminfo
database. E.g. tparm(tigetstr("cup"), 5, 3) could result in
'\033[6;4H', the exact result depending on terminal type.
typeahead(
fd)
Specifies that the file descriptor fd be used for typeahead
checking. If fd is -1, then no typeahead checking is
done.
The curses library does ``line-breakout optimization'' by looking for
typeahead periodically while updating the screen. If input is found,
and it is coming from a tty, the current update is postponed until
refresh or doupdate is called again, allowing faster response to
commands typed in advance. This function allows specifying a different
file descriptor for typeahead checking.
unctrl(
ch)
Returns a string which is a printable representation of the character
ch. Control characters are displayed as a caret followed by the
character, for example as ^C. Printing
characters are left as they are.
ungetch(
ch)
Push ch so the next getch() will return it.
Note:
Only one ch can be pushed before getch()
is called.
ungetmouse(
id, x, y, z, bstate)
Push a KEY_MOUSE event onto the input queue, associating
the given state data with it.
use_env(
flag)
If used, this function should be called before initscr() or
newterm are called. When flag is false, the values of
lines and columns specified in the terminfo database will be
used, even if environment variables LINES and
COLUMNS (used by default) are set, or if curses is running in
a window (in which case default behavior would be to use the window
size if LINES and COLUMNS are not set).
use_default_colors(
)
Allow use of default values for colors on terminals supporting this
feature. Use this to support transparency in your
application. The default color is assigned to the color number -1.
After calling this function,
init_pair(x, curses.COLOR_RED, -1) initializes, for instance,
color pair x to a red foreground color on the default background.
