freebsd man page for termcap

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 library would store a copy of the terminal description in the area refer-
	      enced by this pointer.  However, ncurses stores its terminal 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-addressing.

   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 capability.  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 support 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 capabilities 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
       accommodate 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 ver-
       sions.

       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 compatibility 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 applications.  However, termcap applications' use of those variables is
       poorly documented, e.g., not distinguishing between input and output.  In particular, some applications are reported to declare and/or mod-
       ify ospeed.

       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 ac-
       count these issues:

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

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

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

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

																  curs_termcap(3X)