The tgoto routine expands the given capability using the parameters.
o Because the capability may have padding characters, the output of
tgoto should be passed to tputs rather than some other output func-
- tion such as printf.
+ tion such as printf(3).
o While tgoto is assumed to be used for the two-parameter cursor po-
sitioning capability, termcap applications also use it for single-
@@ -157,7 +157,7 @@
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
@@ -165,6 +165,29 @@
in a system-specific coding to reflect the terminal speed.
+
+ The termcap functions provide no means for freeing memory, because
+ legacy termcap implementations used only the buffer areas provided by
+ the caller via tgetent and tgetstr. Those buffers are unused in ter-
+ minfo.
+
+ On the other hand, terminfo allocates memory. It uses setupterm to re-
+ trieve the data used by tgetent and the functions which return capabil-
+ ity values such as tgetstr. One could use
+
+ del_curterm(cur_term);
+
+
+ to free this memory, but there is an additional complication with
+ ncurses. It uses a fixed-size pool of storage locations, one per set-
+ ting of the TERM variable when tgetent is called. The screen(1) pro-
+ gram relies upon this arrangement, to improve its performance.
+
+ An application which uses only the low-level termcap functions could
+ free the memory using del_curterm, because the pool is freed using oth-
+ er functions (see curs_memleaks(3x)).
+
+
Except where explicitly noted, routines that return an integer return
ERR upon failure and OK (SVr4 only specifies "an integer value other
@@ -268,7 +291,7 @@
was written several years before C was standardized. However, there
were two different termcap.h header files in the BSD sources:
- o One was used internally by the jove editor in 2BSD through 4.4BSD.
+ o One was used internally by the jove editor in 2BSD through 4.4BSD.
It defined global symbols for the termcap variables which it used.
o The other appeared in 4.4BSD Lite Release 2 (mid-1993) as part of
@@ -290,12 +313,12 @@
that instance, it was libedit which differed from BSD termcap.
A copy of GNU termcap 1.3 was bundled with bash in mid-1993, to support
- the readline library.
+ the readline(3) library.
A termcap.h file was provided in ncurses 1.8.1 (November 1993). That
- reflected influence by emacs (rather than jove) and GNU termcap:
+ reflected influence by emacs(1) (rather than jove(1)) and GNU termcap:
- o it provided declarations for a few global symbols used by emacs
+ o it provided declarations for a few global symbols used by emacso it provided function prototypes (using const).
@@ -322,10 +345,11 @@