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curs_termcap(3X)					      curs_termcap(3X)

       PC, UP, BC, ospeed, tgetent, tgetflag, tgetnum, tgetstr,	tgoto, tputs -
       direct curses interface to the terminfo capability database

       #include	<ncursesw/curses.h>
       #include	<term.h>

       extern char PC;
       extern char * UP;
       extern char * BC;
       extern short ospeed;

       int tgetent(char	*bp, const char	*name);
       int tgetflag(char *id);
       int tgetnum(char	*id);
       char *tgetstr(char *id, char **area);
       char *tgoto(const char *cap, int	col, int row);
       int tputs(const char *str, int affcnt, int (*putc)(int));

       These routines are included as a	conversion aid for programs  that  use
       the  termcap  library.	Their parameters are the same and the routines
       are emulated using the terminfo database.  Thus,	they can only be  used
       to  query  the  capabilities  of	entries	for which a terminfo entry has
       been compiled.

       The tgetent routine loads the entry for name.  It returns:

	  1  on	success,

	  0  if	there is no such entry (or that	it is a	generic	 type,	having
	     too little	information for	curses applications to run), and

	  -1 if	the terminfo database could not	be found.

       This differs from the termcap library in	two ways:

	  o   The  emulation  ignores  the buffer pointer bp.  The termcap li-
	      brary would store	a copy of the terminal description in the area
	      referenced  by this pointer.  However, ncurses stores its	termi-
	      nal descriptions in compiled binary form,	which is not the  same

	  o   There is a difference in return codes.  The termcap library does
	      not check	if the terminal	description is marked with the generic
	      capability,  or  if the terminal description has cursor-address-

       The tgetflag routine gets the boolean entry for id, or zero  if	it  is
       not available.

       The  tgetnum  routine gets the numeric entry for	id, or -1 if it	is not

       The tgetstr routine returns the string entry for	id, or zero if	it  is
       not  available.	Use tputs to output the	returned string.  The area pa-
       rameter is used as follows:

	  o   It is assumed to be the address of a pointer to a	buffer managed
	      by the calling application.

	  o   However, ncurses checks to ensure	that area is not NULL, and al-
	      so that the resulting buffer pointer is  not  NULL.   If	either
	      check fails, the area parameter is ignored.

	  o   If  the  checks succeed, ncurses also copies the return value to
	      the buffer pointed to by area, and the area value	will be	updat-
	      ed to point past the null	ending this value.

	  o   The  return  value itself	is an address in the terminal descrip-
	      tion which is loaded into	memory.

       Only the	first two characters of	the id parameter of tgetflag,  tgetnum
       and tgetstr are compared	in lookups.

       The  tgoto routine instantiates the parameters into the given capabili-
       ty.  The	output from this routine is to be passed to tputs.

       The tputs routine is described on the  curs_terminfo(3X)	 manual	 page.
       It can retrieve capabilities by either termcap or terminfo name.

       The  variables PC, UP and BC are	set by tgetent to the terminfo entry's
       data for	pad_char, cursor_up and	backspace_if_not_bs, respectively.  UP
       is  not used by ncurses.	 PC is used in the tdelay_output function.  BC
       is used in the tgoto emulation.	The variable ospeed is set by  ncurses
       in a system-specific coding to reflect the terminal speed.

       Except  where  explicitly noted,	routines that return an	integer	return
       ERR upon	failure	and OK (SVr4 only specifies "an	 integer  value	 other
       than ERR") upon successful completion.

       Routines	that return pointers return NULL on error.

       If  you	call tgetstr to	fetch ca or any	other parameterized string, be
       aware that it will be returned in terminfo notation, not	the older  and
       not-quite-compatible termcap notation.  This will not cause problems if
       all you do with it is call tgoto	or tparm, which	both expand  terminfo-
       style  strings as terminfo.  (The tgoto function, if configured to sup-
       port termcap, will check	if the	string	is  indeed  terminfo-style  by
       looking	for  "%p"  parameters or "$<..>" delays, and invoke a termcap-
       style parser if the string does not appear to be	terminfo).

       Because terminfo	conventions for	representing padding in	 string	 capa-
       bilities	 differ	 from  termcap's,  tputs("50");	will put out a literal
       "50" rather than	busy-waiting for 50 milliseconds.  Cope	with it.

       Note that termcap has nothing analogous to terminfo's sgr string.   One
       consequence  of	this  is that termcap applications assume me (terminfo
       sgr0) does not reset the	alternate character set.  This	implementation
       checks for, and modifies	the data shown to the termcap interface	to ac-
       commodate termcap's limitation in this respect.

       The XSI Curses standard,	Issue 4	describes these	 functions.   However,
       they are	marked TO BE WITHDRAWN and may be removed in future versions.

       Neither	the  XSI Curses	standard nor the SVr4 man pages	documented the
       return values of	tgetent	correctly, though all three were in  fact  re-
       turned  ever  since SVr1.  In particular, an omission in	the XSI	Curses
       documentation has been misinterpreted to	mean that tgetent  returns  OK
       or  ERR.	 Because the purpose of	these functions	is to provide compati-
       bility with the termcap library,	that is	a defect in XCurses, Issue  4,
       Version 2 rather	than in	ncurses.

       External	variables are provided for support of certain termcap applica-
       tions.  However,	termcap	applications' use of those variables is	poorly
       documented, e.g., not distinguishing between input and output.  In par-
       ticular,	some applications are reported to declare  and/or  modify  os-

       The  comment that only the first	two characters of the id parameter are
       used escapes many application developers.  The original BSD 4.2 termcap
       library (and historical relics thereof) did not require a trailing null
       NUL on the parameter name passed	 to  tgetstr,  tgetnum	and  tgetflag.
       Some  applications  assume  that	the termcap interface does not require
       the trailing NUL	for the	parameter name.	 Taking	into account these is-

       o   As  a  special  case,  tgetflag  matched against a single-character
	   identifier provided that was	at the end of  the  terminal  descrip-
	   tion.  You should not rely upon this	behavior in portable programs.
	   This	implementation disallows matches against single-character  ca-
	   pability names.

       o   This	 implementation	 disallows  matches  by	 the termcap interface
	   against extended capability names which are longer than two charac-

       curses(3X), terminfo(5),	term_variables(3X), putc(3).



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