+ 6.1 (Jan 27, 2018)
+ Interface changes:
+
+ + X/Open Curses specifies a "reserved" void* parameter in several
+ functions, saying that it must be NULL. In this release, if the
+ parameter is non-NULL, it is interpreted as a point to an integer
+ containing a color pair. In previous releases, a non-NULL parameter
+ caused an error return. Portable applications are unaffected. Here
+ are the functions which have been extended:
+ attr_get
+ attr_off
+ attr_on
+ attr_set
+ chgat
+ color_set
+ mvchgat
+ mvwchgat
+ slk_attr_off
+ slk_attr_on
+ slk_attr_set
+ wattr_get
+ wattr_on
+ wattr_off
+ wattr_set
+ wchgat
+ wcolor_set
+
+ + the TERMINAL structure declared in <term.h> has been made opaque,
+ and its size increased to handle the increased size of color pair
+ and color value, as well as other numeric capabilities.
+
+ A few applications required change, e.g., to use def_prog_mode;
+ only one application (tack) is known to have a valid reason for
+ accessing these internal details, and that was addressed by the
+ release of tack 1.08 in 2017. Internal functions marked as used
+ by tack will be deprecated in future releases.
+
+ Added extensions:
+
+ + Several new functions were added to manipulate extended color pairs
+ and color values. These include:
+ alloc_pair
+ extended_color_content
+ extended_pair_content
+ extended_slk_color
+ find_pair
+ free_pair
+ init_extended_color
+ init_extended_pair
+ reset_color_pairs
+
+ as well as corresponding sp-functions.
+
+ + A new terminfo capability "RGB" tells the ncurses library that the
+ color values are red/green/blue, to eliminate the need for palettes
+ in that special case for the color_content function.
+
+ Added internal functions (other than "_sp" variants):
+ _nc_copy_termtype2
+ _nc_export_termtype2
+ _nc_fallback2
+ _nc_find_prescr
+ _nc_forget_prescr
+ _nc_free_termtype2
+ _nc_read_entry2
+ _nc_write_object
+
+ Removed internal functions:
+ _nc_check_termtype
+ _nc_resolve_uses
+
+ Modified internal functions:
+
+ + symbols are used by tic/infocmp/toe:
+ _nc_align_termtype - change parameters to TERMTYPE2*
+ _nc_check_termtype2 - change parameter to TERMTYPE2*
+ _nc_read_file_entry - change parameter to TERMTYPE2*
+ _nc_read_termtype - change parameter to TERMTYPE2*
+ _nc_trim_sgr0 - change parameter to TERMTYPE2*
+ _nc_write_entry - change parameter to TERMTYPE2*
+
+ + symbols used only within the library:
+ _nc_fallback - change return type to TERMTYPE2*
+ _nc_init_termtype - change parameter to TERMTYPE2*
+
+ 6.0 (Aug 08, 2015)
+ Interface changes:
+
+ + The 6.0 ABI modifies the defaults for these configure options:
+ --enable-const
+ --enable-ext-colors
+ --enable-ext-mouse
+ --enable-ext-putwin
+ --enable-interop
+ --enable-lp64
+ --enable-sp-funcs
+ --with-chtype=uint32_t
+ --with-mmask_t=uint32_t
+ --with-tparm-arg=intptr_t
+
+ + ncurses supports symbol versioning. If you use this feature, about
+ half of the "_nc_" private symbols are changed to local symbols.
+
+ + a few applications may need to explicitly flush the standard output
+ when switching between printf's and (curses) printw.
+
+ Added extensions:
+
+ + use_tioctl is an improvement over use_env
+
+ + added wgetdelay to support the NCURSES_OPAQUE feature.
+
+ Added internal functions (other than "_sp" variants):
+ _nc_init_termtype
+ _nc_mvcur
+ _nc_putchar
+ _nc_setenv_num
+ _nc_trace_mmask_t
+
+ Removed internal functions:
+ none
+
+ Modified internal functions:
+ _nc_do_color - change parameters from short/bool to int
+ _nc_keypad - change parameter from bool to int
+ _nc_setupscreen - change parameter from bool to int
+ _nc_signal_handler - change parameter from bool to int
+
+ 5.9 (Apr 04, 2011)
+ 5.8 (Feb 26, 2011)
+ Interface changes:
+
+ + add an alternate library configuration, i.e., "terminal driver" to
+ support port to Windows, built with MinGW. There are two drivers
+ (terminfo and Windows console). The terminfo driver works on other
+ platforms.
+
+ + add a new set of functions which accept a SCREEN* parameter, in
+ contrast with the original set which use the global value "sp".
+ By default, these names end with "_sp", and are otherwise
+ functionally identical with the originals.
+
+ In addition to the "_sp" functions, there are a few new functions
+ associated with this feature: ceiling_panel, ground_panel,
+ new_prescr.
+
+ If the library is not built with the sp-funcs extension, there
+ are no related interface changes.
+
+ + add tiparm function based on review of X/Open Curses Issue 7.
+
+ + change internal _nc_has_mouse function to public has_mouse function
+
+ Added extensions:
+
+ + add a few more functions to support the NCURSES_OPAQUE feature:
+ get_escdelay, is_pad, is_subwin
+
+ Added internal functions (other than "_sp" variants):
+ _nc_curscr_of
+ _nc_format_slks
+ _nc_get_alias_table
+ _nc_get_hash_info
+ _nc_insert_wch
+ _nc_newscr_of
+ _nc_outc_wrapper
+ _nc_retrace_char
+ _nc_retrace_int_attr_t
+ _nc_retrace_mmask_t
+ _nc_setup_tinfo
+ _nc_stdscr_of
+ _nc_tinfo_cmdch
+
+ Removed internal functions:
+ _nc_makenew (some configurations replace by _nc_makenew_sp)
+
+ Modified internal functions:
+ _nc_UpdateAttrs
+ _nc_get_hash_table
+ _nc_has_mouse
+ _nc_insert_ch
+ _nc_wgetch
+
+ 5.7 (November 2, 2008)
+ Interface changes:
+
+ + generate linkable stubs for some macros:
+ getattrs
+
+ + Add new library configuration for tic-library (the non-curses portion
+ of the ncurses library used for the tic program as well as some
+ others such as tack. There is no API change, but makefiles would be
+ changed to use the tic-library built separately.
+
+ tack, distributed separately from ncurses, uses some of the internal
+ _nc_XXX functions, which are declared in the tic.h header file.
+
+ The reason for providing this separate library is that none of the
+ functions in it are suitable for threaded applications.
+
+ + Add new library configuration (ncursest, ncurseswt) which provides
+ rudimentary support for POSIX threads. This introduces opaque
+ access functions to the WINDOW structure and adds a parameter to
+ several internal functions.
+
+ + move most internal variables (except tic-library) into data blocks
+ _nc_globals and _nc_prescreen to simplify analysis. Those were
+ globally accessible, but since they were not part of the documented
+ API, there is no ABI change.
+
+ + changed static tables of strings to be indices into long strings, to
+ improve startup performance. This changes parameter lists for some
+ of the internal functions.
+
+ Added extensions:
+
+ + add NCURSES_OPAQUE definition in curses.h to control whether internal
+ details of the WINDOW structure are visible to an application. This
+ is always defined when the threaded library is built, and is optional
+ otherwise. New functions for this: is_cleared, is_idcok, is_idlok,
+ is_immedok, is_keypad, is_leaveok, is_nodelay, is_notimeout,
+ is_scrollok, is_syncok, wgetparent and wgetscrreg.
+
+ + the threaded library (ncursest) also disallows direct updating of
+ global curses-level variables, providing functions (via macros) for
+ obtaining their value. A few of those variables can be modified by
+ the application, using new functions: set_escdelay, set_tabsize
+
+ + added functions use_window() and use_screen() which wrap a mutex
+ (if threading is configured) around a call to a user-supplied
+ function.
+
+ Added internal functions:
+ _nc_get_alias_table
+ _nc_get_screensize
+ _nc_keyname
+ _nc_screen_of
+ _nc_set_no_padding
+ _nc_tracechar
+ _nc_tracemouse
+ _nc_unctrl
+ _nc_ungetch
+
+ These are used for leak-testing, and are stubs for
+ ABI compatibility when ncurses is not configured for that
+ using the --disable-leaks configure script option:
+
+ _nc_free_and_exit
+ _nc_leaks_tinfo
+
+ Removed internal functions:
+ none
+
+ Modified internal functions:
+ _nc_fifo_dump
+ _nc_find_entry
+ _nc_handle_sigwinch
+ _nc_init_keytry
+ _nc_keypad
+ _nc_locale_breaks_acs
+ _nc_timed_wait
+ _nc_update_screensize
+
+ Use new typedef TRIES to replace "struct tries":
+
+ _nc_add_to_try
+ _nc_expand_try
+ _nc_remove_key
+ _nc_remove_string
+ _nc_trace_tries
+