slk_init, slk_set, slk_wset, slk_refresh, slk_noutrefresh, slk_label,
   slk_clear, slk_restore, slk_touch, slk_attron, slk_attrset,
   slk_attroff, slk_attr_on, slk_attr_set, slk_attr_off, slk_attr,
   slk_color - curses soft label routines


   #include <curses.h>

   int slk_init(int fmt);
   int slk_set(int labnum, const char *label, int fmt);
   int slk_refresh(void);
   int slk_noutrefresh(void);
   char *slk_label(int labnum);
   int slk_clear(void);
   int slk_restore(void);
   int slk_touch(void);
   int slk_attron(const chtype attrs);
   int slk_attroff(const chtype attrs);
   int slk_attrset(const chtype attrs);
   int slk_attr_on(attr_t attrs, void* opts);
   int slk_attr_off(const attr_t attrs, void * opts);
   int slk_attr_set(const attr_t attrs, short color_pair, void* opts);
   attr_t slk_attr(void);
   int slk_color(short color_pair);
   int slk_wset(int labnum, const wchar_t *label, int fmt);


   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  today's  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.

   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

          0  indicates a 3-2-3 arrangement of the labels.

          1  indicates a 4-4 arrangement

          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.

   The slk_set routine (and the slk_wset routine  for  the  wide-character
   library) has three parameters:

               is the label number, from 1 to 8 (12 for fmt in slk_init is
               2 or 3);

               is be the string to put on the label, up to eight (five for
               fmt  in  slk_init  is 2 or 3) characters in length.  A null
               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.

   The slk_refresh and slk_noutrefresh routines correspond to the wrefresh
   and wnoutrefresh routines.

   The  slk_label  routine  returns  the  current  label  for label number
   labnum, with leading and trailing blanks stripped.

   The slk_clear routine clears the soft labels from the screen.

   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
   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.  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_color routine corresponds to color_set.  It has an effect  only
   if soft labels are simulated on the bottom line of the screen.


   These  routines return ERR upon failure and OK (SVr4 specifies only "an
   integer value other than ERR") upon successful completion.

   X/Open defines no error conditions.  In this implementation

               returns the attribute used for the soft keys.

          slk_attroff, slk_attron, slk_clear, slk_noutrefresh,
          slk_refresh, slk_touch
               return  an  error  if the terminal or the softkeys were not

               returns an error if the terminal or the softkeys  were  not

               returns  an  error if the terminal or the softkeys were not
               initialized,  or  the  color  pair  is  outside  the  range
               0..COLOR_PAIRS-1, or opts is not null.

               returns  an  error if the terminal or the softkeys were not
               initialized,  or  the  color  pair  is  outside  the  range

               returns  an  error  if  the format parameter is outside the
               range 0..3.

               returns NULL on error.

               returns an error if the terminal or the softkeys  were  not
               initialized,  or  the labnum parameter is outside the range
               of label counts, or if the format parameter is outside  the
               range   0..2,  or  if  memory  for  the  labels  cannot  be


   Most applications would  use  slk_noutrefresh  because  a  wrefresh  is
   likely to follow soon.


   The  XSI  Curses  standard,  Issue  4,  describes  these functions.  It
   changes the  argument  type  of  the  attribute-manipulation  functions
   slk_attron,  slk_attroff,  slk_attrset  to  be  attr_t,  and adds const
   qualifiers.  The format codes 2 and 3 for slk_init() and  the  function
   slk_attr are specific to ncurses.


   ncurses(3NCURSES),          attr(3NCURSES),          initscr(3NCURSES),
   refresh(3NCURSES), curses_variables(3NCURSES).



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