- The slk* functions manipulate the set of soft function-key labels that
- exist on many terminals. For those terminals that do not have soft
- labels, curses takes over the bottom line of stdscr, reducing the size
- of stdscr and the variable LINES. curses standardizes on eight labels
- of up to eight characters each. In addition to this, the ncurses
- implementation supports a mode where it simulates 12 labels of up to
- five characters each. This is useful for PC-like enduser devices.
- ncurses simulates this mode by taking over up to two lines at the
- bottom of the screen; it does not try to use any hardware support for
- this mode.
+ These functions manipulate the soft function key labels that some
+ hardware terminals support. For those terminals that do not have soft
+ labels, curses takes over the bottom line of stdscr, reducing its
+ vertical size and the value of LINES by one. By default, curses uses
+ eight labels of up to eight characters each.
+
+ ncurses furthermore supports a mode comprising twelve labels of up to
+ five characters each, following a convention associated with the IBM
+ PC/AT keyboard. ncurses simulates this mode by taking over up to two
+ lines at the bottom of the screen; it does not try to use any hardware
+ support for this mode.
- The slk_init routine must be called before initscr or newterm is
- called. If initscr eventually uses a line from stdscr to emulate the
- soft labels, then fmt determines how the labels are arranged on the
- screen:
+ slk_init must be called before initscr or newterm. If initscr
+ eventually uses a line from stdscr to emulate the soft labels, then fmt
+ determines how the labels are arranged on the screen.
- 0 indicates a 3-2-3 arrangement of the labels.
+ 0 indicates a 3-2-3 arrangement of the labels.
- 1 indicates a 4-4 arrangement
+ 1 indicates a 4-4 arrangement
- 2 indicates the PC-like 4-4-4 mode.
+ 2 indicates the PC-like 4-4-4 mode.
- 3 is again the PC-like 4-4-4 mode, but in addition an index line is
- generated, helping the user to identify the key numbers easily.
+ 3 is again the PC-like 4-4-4 mode, but in addition an index line is
+ generated, helping the user to associate each label with its
+ numbered function key. LINES and the vertical size of stdscr are
+ further reduced.
- The slk_set routine (and the slk_wset routine for the wide-character
- library) has three parameters:
+ Populate the labels with normal strings (slk_set) or wide-character
+ strings (slk_wset). Each function takes three parameters.
- labnum
- is the label number, from 1 to 8 (12 if fmt in slk_init is 2 or
+ labnum is the label number, from 1 to 8 (12 if fmt in slk_init is 2 or
3);
- label
- is be the string to put on the label, up to eight (five if fmt
- in slk_init is 2 or 3) characters in length. A null string or
+ label is be the string to put on the label, up to eight (five if fmt
+ in slk_init is 2 or 3) characters in length. A empty string or
a null pointer sets up a blank label.
- fmt is either 0, 1, or 2, indicating whether the label is to be
- left-justified, centered, or right-justified, respectively,
- within the label.
+ align is 0, 1, or 2, aligning label to the left, center, or right,
+ respectively, within the 8 (5) character cells housing it.
- The slk_label routine returns the current label for label number
- labnum, with leading and trailing blanks stripped.
+ slk_label obtains the string assigned to label number labnum, with any
+ leading and trailing blanks stripped.
-
+ slk_refresh and slk_noutrefresh affect the soft key label lines as
+ wrefresh and wnoutrefresh do the curses window.
The slk_clear routine clears the soft labels from the screen.
- The slk_restore routine restores the soft labels to the screen after a
+ The slk_restore routine restores the soft labels to the screen after a
slk_clear has been performed.
- The slk_touch routine forces all the soft labels to be output the next
+ The slk_touch routine forces all the soft labels to be output the next
time a slk_noutrefresh is performed.
-
- The slk_attron, slk_attrset, slk_attroff and slk_attr routines
- correspond to attron, attrset, attroff and attr_get, respectively.
- They have an effect only if soft labels are simulated on the bottom
- line of the screen. The default highlight for soft keys is A_STANDOUT
- (as in System V curses, which does not document this fact).
+
+ The slk_attron, slk_attrset, slk_attroff, and slk_attr routines
+ correspond to attron, attrset, attroff, and attr_get, respectively.
+ They have an effect only if soft labels are simulated on the bottom
+ line of the screen. The default highlight for soft key labels is
+ A_STANDOUT (as in System V curses, which does not document this fact).
- The slk_color routine corresponds to color_set. It has an effect only
+ The slk_color routine corresponds to color_set. It has an effect only
if soft labels are simulated on the bottom line of the screen.
- Because slk_color accepts only short (signed 16-bit integer) values,
- this implementation provides extended_slk_color which accepts an
- integer value, e.g., 32-bits.
+ Because slk_color accepts only short (signed 16-bit integer) values,
+ this implementation provides extended_slk_color, which accepts an int
+ value of at least 32 bits.
- These routines return ERR upon failure and OK (SVr4 specifies only "an
- integer value other than ERR") upon successful completion.
+ Routines that return an integer return ERR upon failure and OK (SVr4
+ specifies only "an integer value other than ERR") upon successful
+ completion.
+
+ X/Open Curses defines no error conditions.
- X/Open defines no error conditions. In this implementation
+ In this implementation
slk_attr
returns the attribute used for the soft keys.
@@ -205,62 +207,37 @@
0..2, or if memory for the labels cannot be allocated.
-
- X/Open curses documents the opts argument as reserved for future use,
- saying that it must be null. This implementation uses that parameter
- in ABI 6 for the functions which have a color-pair parameter to support
+ X/Open Curses documents the opts argument as reserved for future use,
+ saying that it must be null. This implementation uses that parameter
+ in ABI 6 for the functions which have a color pair parameter to support
extended color pairs.
- For functions which modify the color, e.g., slk_attr_set, if opts is
- set it is treated as a pointer to int, and used to set the color
- pair instead of the short pair parameter.
-
-
-
- Most applications would use slk_noutrefresh because a wrefresh is
- likely to follow soon.
+ For functions which modify the color, e.g., slk_attr_set, if opts is
+ set it is treated as a pointer to int, and used to set the color pair
+ instead of the short pair parameter.
- The XSI curses standard, Issue 4, described the soft-key functions,
- with some differences from SVr4 curses:
+ X/Open Curses, Issue 4 describes these functions, with some differences
+ from SVr4 curses:
- o It added functions like the SVr4 attribute-manipulation functions
- slk_attron, slk_attroff, slk_attrset, but which use attr_t
- parameters (rather than chtype), along with a reserved opts
+ o X/Open added functions like the SVr4 attribute-manipulation
+ functions slk_attron, slk_attroff, and slk_attrset, but which use
+ attr_t parameters (rather than chtype), along with a reserved opts
parameter.
Two of these new functions (unlike the SVr4 functions) have no
provision for color: slk_attr_on and slk_attr_off.
- The third function (slk_attr_set) has a color-pair parameter.
+ The third function (slk_attr_set) has a color pair parameter.
- o It added const qualifiers to parameters (unnecessarily), and
+ o It added const qualifiers to parameters (unnecessarily), and
o It added slk_color.
@@ -296,22 +273,47 @@
The function slk_attr was added by ncurses in 1996.
- X/Open curses does not specify a limit for the number of colors and
- color pairs which a terminal can support. However, in its use of short
+ X/Open Curses does not specify a limit for the number of colors and
+ color pairs which a terminal can support. However, in its use of short
for the parameters, it carries over SVr4's implementation detail for
the compiled terminfo database, which uses signed 16-bit numbers. This
implementation provides extended versions of those functions which use
- int parameters, allowing applications to use larger color- and pair-
+ int parameters, allowing applications to use larger color- and pair-
numbers.
+