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curs_termcap(3X)					      curs_termcap(3X)

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

SYNOPSIS
       #include	<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));

DESCRIPTION
       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.

   INITIALIZATION
       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
	      thing.

	  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-
	      ing.

   CAPABILITY VALUES
       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
       available.

       The tgetstr routine returns the string entry for	id, or zero if	it  is
       not  available.	 Use  tputs to output the returned string.  The	return
       value will also be copied to the	buffer pointed to  by  area,  and  the
       area value will be updated to point past	the null ending	this value.

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

   FORMATTING CAPABILITIES
       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.

   GLOBAL VARIABLES
       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.

RETURN VALUE
       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.

BUGS
       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.

PORTABILITY
       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-
       peed.

       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-
       sues:

       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-
	   ters.

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

       http://invisible-island.net/ncurses/tctest.html

							      curs_termcap(3X)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | BUGS | PORTABILITY | SEE ALSO

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