X-Git-Url: https://ncurses.scripts.mit.edu/?p=ncurses.git;a=blobdiff_plain;f=doc%2Fhtml%2Fman%2Fncurses.3x.html;h=bda5c0ccd28e723041dc734a06c8b08fdb972581;hp=b1f5bad6408d9b1827f99c607d6fff2f06535ab3;hb=c0f109a299a82a33c16bd7af942a12ce9aefaaf0;hpb=b793748293cd1a764b1a858455399ad899b5a8a1 diff --git a/doc/html/man/ncurses.3x.html b/doc/html/man/ncurses.3x.html index b1f5bad6..bda5c0cc 100644 --- a/doc/html/man/ncurses.3x.html +++ b/doc/html/man/ncurses.3x.html @@ -1,7 +1,8 @@ - + ncurses 3x - + @@ -59,7 +60,7 @@ method of updating character screens with reasonable optimization. This implementation is "new curses" (ncurses) and is the approved replacement for 4.4BSD classic curses, which has been discontinued. - This describes ncurses version 6.0 (patch 20170520). + This describes ncurses version 6.2 (patch 20200314). The ncurses library emulates the curses library of System V Release 4 UNIX, and XPG4 (X/Open Portability Guide) curses (also known as XSI @@ -92,7 +93,7 @@ The library uses the locale which the calling program has initialized. That is normally done with setlocale: - setlocale(LC_ALL, ""); + setlocale(LC_ALL, ""); If the locale is not initialized, the library assumes that characters are printable as in ISO-8859-1, to work with certain legacy programs. @@ -108,13 +109,13 @@ screen oriented programs want this), the following sequence should be used: - initscr(); cbreak(); noecho(); + initscr(); cbreak(); noecho(); Most programs would additionally use the sequence: - nonl(); - intrflush(stdscr, FALSE); - keypad(stdscr, TRUE); + nonl(); + intrflush(stdscr, FALSE); + keypad(stdscr, TRUE); Before a curses program is run, the tab stops of the terminal should be set and its initialization strings, if defined, must be output. This @@ -176,17 +177,17 @@ standard place. For example, if TERM is set to att4424, then the com- piled terminal definition is found in - /usr/share/terminfo/a/att4424. + /usr/share/terminfo/a/att4424. (The a is copied from the first letter of att4424 to avoid creation of huge directories.) However, if TERMINFO is set to $HOME/myterms, curses first checks - $HOME/myterms/a/att4424, + $HOME/myterms/a/att4424, and if that fails, it then checks - /usr/share/terminfo/a/att4424. + /usr/share/terminfo/a/att4424. This is useful for developing experimental definitions or when write permission in /usr/share/terminfo is not available. @@ -258,24 +259,27 @@ Each cell (row and column) in a WINDOW is stored as a cchar_t. + The setcchar(3x) and getcchar(3x) functions store and + retrieve the data from a cchar_t structure. + wchar_t - stores a "wide" character. Like chtype, this may be an + stores a "wide" character. Like chtype, this may be an integer. wint_t - stores a wchar_t or WEOF - not the same, though both may + stores a wchar_t or WEOF - not the same, though both may have the same size. - The "wide" library provides new functions which are analogous - to functions in the "normal" library. There is a naming con- - vention which relates many of the normal/wide variants: a "_w" + The "wide" library provides new functions which are analogous + to functions in the "normal" library. There is a naming con- + vention which relates many of the normal/wide variants: a "_w" is inserted into the name. For example, waddch becomes wadd_wch.

Routine Name Index

-       The  following table lists each curses routine and the name of the man-
-       ual page on which it is  described.   Routines  flagged  with  "*"  are
+       The following table lists each curses routine and the name of the  man-
+       ual  page  on  which  it  is  described.  Routines flagged with "*" are
        ncurses-specific, not described by XPG4 or present in SVr4.
 
                     curses Routine Name      Manual Page Name
@@ -309,10 +313,10 @@
                     attr_off                 curs_attr(3x)
                     attr_on                  curs_attr(3x)
                     attr_set                 curs_attr(3x)
+
                     attroff                  curs_attr(3x)
                     attron                   curs_attr(3x)
                     attrset                  curs_attr(3x)
-
                     baudrate                 curs_termattrs(3x)
                     beep                     curs_beep(3x)
                     bkgd                     curs_bkgd(3x)
@@ -375,10 +379,10 @@
                     getcurx                  curs_legacy(3x)*
                     getcury                  curs_legacy(3x)*
                     getmaxx                  curs_legacy(3x)*
+
                     getmaxy                  curs_legacy(3x)*
                     getmaxyx                 curs_getyx(3x)
                     getmouse                 curs_mouse(3x)*
-
                     getn_wstr                curs_get_wstr(3x)
                     getnstr                  curs_getstr(3x)
                     getparx                  curs_legacy(3x)*
@@ -441,10 +445,10 @@
                     key_defined              key_defined(3x)*
                     key_name                 curs_util(3x)
                     keybound                 keybound(3x)*
+
                     keyname                  curs_util(3x)
                     keyok                    keyok(3x)*
                     keypad                   curs_inopts(3x)
-
                     killchar                 curs_termattrs(3x)
                     killwchar                curs_termattrs(3x)
                     leaveok                  curs_outopts(3x)
@@ -507,10 +511,10 @@
                     mvwaddnwstr              curs_addwstr(3x)
                     mvwaddstr                curs_addstr(3x)
                     mvwaddwstr               curs_addwstr(3x)
+
                     mvwchgat                 curs_attr(3x)
                     mvwdelch                 curs_delch(3x)
                     mvwget_wch               curs_get_wch(3x)
-
                     mvwget_wstr              curs_get_wstr(3x)
                     mvwgetch                 curs_getch(3x)
                     mvwgetn_wstr             curs_get_wstr(3x)
@@ -573,10 +577,10 @@
                     restartterm              curs_terminfo(3x)
                     ripoffline               curs_kernel(3x)
                     savetty                  curs_kernel(3x)
+
                     scanw                    curs_scanw(3x)
                     scr_dump                 curs_scr_dump(3x)
                     scr_init                 curs_scr_dump(3x)
-
                     scr_restore              curs_scr_dump(3x)
                     scr_set                  curs_scr_dump(3x)
                     scrl                     curs_scroll(3x)
@@ -639,10 +643,10 @@
                     use_default_colors       default_colors(3x)*
                     use_env                  curs_util(3x)
                     use_extended_names       curs_extend(3x)*
+
                     use_legacy_coding        legacy_coding(3x)*
-                    use_tioctl               curs_util(3x)
+                    use_tioctl               curs_util(3x)*
                     vid_attr                 curs_terminfo(3x)
-
                     vid_puts                 curs_terminfo(3x)
                     vidattr                  curs_terminfo(3x)
                     vidputs                  curs_terminfo(3x)
@@ -705,10 +709,10 @@
                     winch                    curs_inch(3x)
                     winchnstr                curs_inchstr(3x)
                     winchstr                 curs_inchstr(3x)
+
                     winnstr                  curs_instr(3x)
                     winnwstr                 curs_inwstr(3x)
                     wins_nwstr               curs_ins_wstr(3x)
-
                     wins_wch                 curs_ins_wch(3x)
                     wins_wstr                curs_ins_wstr(3x)
                     winsch                   curs_insch(3x)
@@ -740,31 +744,31 @@
 
 
 

RETURN VALUE

-       Routines  that return an integer return ERR upon failure and an integer
+       Routines that return an integer return ERR upon failure and an  integer
        value other than ERR upon successful completion, unless otherwise noted
        in the routine descriptions.
 
-       As  a  general rule, routines check for null pointers passed as parame-
+       As a general rule, routines check for null pointers passed  as  parame-
        ters, and handle this as an error.
 
-       All macros return  the  value  of  the  w  version,  except  setscrreg,
-       wsetscrreg,  getyx,  getbegyx,  and  getmaxyx.   The  return  values of
-       setscrreg, wsetscrreg, getyx,  getbegyx,  and  getmaxyx  are  undefined
-       (i.e.,  these  should  not be used as the right-hand side of assignment
+       All  macros  return  the  value  of  the  w  version, except setscrreg,
+       wsetscrreg, getyx,  getbegyx,  and  getmaxyx.   The  return  values  of
+       setscrreg,  wsetscrreg,  getyx,  getbegyx,  and  getmaxyx are undefined
+       (i.e., these should not be used as the right-hand  side  of  assignment
        statements).
 
        Routines that return pointers return NULL on error.
 
 
 

ENVIRONMENT

-       The following environment symbols are useful for customizing  the  run-
-       time  behavior  of  the  ncurses library.  The most important ones have
+       The  following  environment symbols are useful for customizing the run-
+       time behavior of the ncurses library.  The  most  important  ones  have
        been already discussed in detail.
 
 
 

CC command-character

-       When set, change occurrences of the command_character (i.e., the  cmdch
-       capability)  of  the loaded terminfo entries to the value of this vari-
+       When  set, change occurrences of the command_character (i.e., the cmdch
+       capability) of the loaded terminfo entries to the value of  this  vari-
        able.  Very few terminfo entries provide this feature.
 
        Because this name is also used in development environments to represent
@@ -773,34 +777,34 @@
 
 
 

BAUDRATE

-       The debugging library checks this environment variable when the  appli-
-       cation  has  redirected output to a file.  The variable's numeric value
-       is used for the baudrate.  If no value is  found,  ncurses  uses  9600.
-       This  allows  testers to construct repeatable test-cases that take into
+       The  debugging library checks this environment variable when the appli-
+       cation has redirected output to a file.  The variable's  numeric  value
+       is  used  for  the  baudrate.  If no value is found, ncurses uses 9600.
+       This allows testers to construct repeatable test-cases that  take  into
        account costs that depend on baudrate.
 
 
 

COLUMNS

        Specify the width of the screen in characters.  Applications running in
-       a  windowing  environment  usually  are able to obtain the width of the
-       window in which they are executing.  If neither the COLUMNS  value  nor
-       the  terminal's  screen  size is available, ncurses uses the size which
+       a windowing environment usually are able to obtain  the  width  of  the
+       window  in  which they are executing.  If neither the COLUMNS value nor
+       the terminal's screen size is available, ncurses uses  the  size  which
        may be specified in the terminfo database (i.e., the cols capability).
 
-       It is important that your  application  use  a  correct  size  for  the
-       screen.   This  is  not always possible because your application may be
-       running on a host which does not honor NAWS (Negotiations About  Window
-       Size),  or  because  you are temporarily running as another user.  How-
-       ever, setting COLUMNS and/or LINES overrides the library's use  of  the
+       It  is  important  that  your  application  use  a correct size for the
+       screen.  This is not always possible because your  application  may  be
+       running  on a host which does not honor NAWS (Negotiations About Window
+       Size), or because you are temporarily running as  another  user.   How-
+       ever,  setting  COLUMNS and/or LINES overrides the library's use of the
        screen size obtained from the operating system.
 
-       Either  COLUMNS  or LINES symbols may be specified independently.  This
-       is mainly useful to circumvent legacy misfeatures of terminal  descrip-
+       Either COLUMNS or LINES symbols may be specified  independently.   This
+       is  mainly useful to circumvent legacy misfeatures of terminal descrip-
        tions, e.g., xterm which commonly specifies a 65 line screen.  For best
-       results, lines and cols should not be specified in a terminal  descrip-
+       results,  lines and cols should not be specified in a terminal descrip-
        tion for terminals which are run as emulations.
 
-       Use  the  use_env  function  to disable all use of external environment
+       Use the use_env function to disable all  use  of  external  environment
        (but not including system calls) to determine the screen size.  Use the
        use_tioctl function to update COLUMNS or LINES to match the screen size
        obtained from system calls or the terminal database.
@@ -808,35 +812,35 @@
 
 

ESCDELAY

        Specifies the total time, in milliseconds, for which ncurses will await
-       a  character  sequence,  e.g., a function key.  The default value, 1000
-       milliseconds, is enough for most uses.  However, it is made a  variable
+       a character sequence, e.g., a function key.  The  default  value,  1000
+       milliseconds,  is enough for most uses.  However, it is made a variable
        to accommodate unusual applications.
 
-       The  most common instance where you may wish to change this value is to
-       work with slow hosts, e.g., running on a network.  If the  host  cannot
-       read  characters rapidly enough, it will have the same effect as if the
-       terminal did not send characters  rapidly  enough.   The  library  will
+       The most common instance where you may wish to change this value is  to
+       work  with  slow hosts, e.g., running on a network.  If the host cannot
+       read characters rapidly enough, it will have the same effect as if  the
+       terminal  did  not  send  characters  rapidly enough.  The library will
        still see a timeout.
 
-       Note  that  xterm  mouse  events  are built up from character sequences
+       Note that xterm mouse events are  built  up  from  character  sequences
        received from the xterm.  If your application makes heavy use of multi-
-       ple-clicking,  you  may wish to lengthen this default value because the
-       timeout applies to the composed multi-click event as well as the  indi-
+       ple-clicking, you may wish to lengthen this default value  because  the
+       timeout  applies to the composed multi-click event as well as the indi-
        vidual clicks.
 
        In addition to the environment variable, this implementation provides a
-       global variable with the same name.  Portable applications  should  not
-       rely  upon  the  presence  of  ESCDELAY in either form, but setting the
-       environment variable rather than the global variable  does  not  create
+       global  variable  with the same name.  Portable applications should not
+       rely upon the presence of ESCDELAY in  either  form,  but  setting  the
+       environment  variable  rather  than the global variable does not create
        problems when compiling an application.
 
 
 

HOME

-       Tells  ncurses where your home directory is.  That is where it may read
+       Tells ncurses where your home directory is.  That is where it may  read
        and write auxiliary terminal descriptions:
 
-         $HOME/.termcap
-         $HOME/.terminfo
+           $HOME/.termcap
+           $HOME/.terminfo
 
 
 

LINES

@@ -846,12 +850,12 @@
 
 

MOUSE_BUTTONS_123

        This applies only to the OS/2 EMX port.  It specifies the order of but-
-       tons on the mouse.  OS/2 numbers a 3-button mouse  inconsistently  from
+       tons  on  the mouse.  OS/2 numbers a 3-button mouse inconsistently from
        other platforms:
 
-         1 = left
-         2 = right
-         3 = middle.
+           1 = left
+           2 = right
+           3 = middle.
 
        This variable lets you customize the mouse.  The variable must be three
        numeric digits 1-3 in any order, e.g., 123 or 321.  If it is not speci-
@@ -859,32 +863,32 @@
 
 
 

NCURSES_ASSUMED_COLORS

-       Override  the compiled-in assumption that the terminal's default colors
-       are white-on-black (see default_colors(3x)).  You  may  set  the  fore-
-       ground  and  background  color values with this environment variable by
-       proving a 2-element list: foreground,background.  For example, to  tell
-       ncurses  to  not assume anything about the colors, set this to "-1,-1".
-       To make it green-on-black, set it to "2,0".  Any  positive  value  from
+       Override the compiled-in assumption that the terminal's default  colors
+       are  white-on-black  (see  default_colors(3x)).   You may set the fore-
+       ground and background color values with this  environment  variable  by
+       proving  a 2-element list: foreground,background.  For example, to tell
+       ncurses to not assume anything about the colors, set this  to  "-1,-1".
+       To  make  it  green-on-black, set it to "2,0".  Any positive value from
        zero to the terminfo max_colors value is allowed.
 
 
 

NCURSES_CONSOLE2

        This applies only to the MinGW port of ncurses.
 
-       The  Console2 program's handling of the Microsoft Console API call Cre-
-       ateConsoleScreenBuffer is defective.  Applications which use this  will
-       hang.   However,  it is possible to simulate the action of this call by
-       mapping coordinates,  explicitly  saving  and  restoring  the  original
-       screen  contents.   Setting the environment variable NCGDB has the same
+       The Console2 program's handling of the Microsoft Console API call  Cre-
+       ateConsoleScreenBuffer  is defective.  Applications which use this will
+       hang.  However, it is possible to simulate the action of this  call  by
+       mapping  coordinates,  explicitly  saving  and  restoring  the original
+       screen contents.  Setting the environment variable NCGDB has  the  same
        effect.
 
 
 

NCURSES_GPM_TERMS

        This applies only to ncurses configured to use the GPM interface.
 
-       If present, the environment variable is a list of one or more  terminal
-       names  against which the TERM environment variable is matched.  Setting
-       it to an empty value disables the GPM  interface;  using  the  built-in
+       If  present, the environment variable is a list of one or more terminal
+       names against which the TERM environment variable is matched.   Setting
+       it  to  an  empty  value disables the GPM interface; using the built-in
        support for xterm, etc.
 
        If the environment variable is absent, ncurses will attempt to open GPM
@@ -892,38 +896,38 @@
 
 
 

NCURSES_NO_HARD_TABS

-       Ncurses may use tabs as part of the cursor movement  optimization.   In
-       some  cases,  your  terminal driver may not handle these properly.  Set
-       this environment variable to disable the feature.  You can also  adjust
+       Ncurses  may  use tabs as part of the cursor movement optimization.  In
+       some cases, your terminal driver may not handle  these  properly.   Set
+       this  environment variable to disable the feature.  You can also adjust
        your stty settings to avoid the problem.
 
 
 

NCURSES_NO_MAGIC_COOKIE

-       Some  terminals  use a magic-cookie feature which requires special han-
+       Some terminals use a magic-cookie feature which requires  special  han-
        dling to make highlighting and other video attributes display properly.
-       You  can suppress the highlighting entirely for these terminals by set-
+       You can suppress the highlighting entirely for these terminals by  set-
        ting this environment variable.
 
 
 

NCURSES_NO_PADDING

-       Most of the terminal descriptions in the terminfo database are  written
-       for  real  "hardware"  terminals.   Many  people use terminal emulators
+       Most  of the terminal descriptions in the terminfo database are written
+       for real "hardware" terminals.   Many  people  use  terminal  emulators
        which run in a windowing environment and use curses-based applications.
-       Terminal  emulators  can  duplicate  all  of the important aspects of a
-       hardware terminal, but they do not  have  the  same  limitations.   The
-       chief  limitation  of  a  hardware terminal from the standpoint of your
-       application is the management of  dataflow,  i.e.,  timing.   Unless  a
-       hardware  terminal  is  interfaced  into a terminal concentrator (which
+       Terminal emulators can duplicate all of  the  important  aspects  of  a
+       hardware  terminal,  but  they  do  not have the same limitations.  The
+       chief limitation of a hardware terminal from  the  standpoint  of  your
+       application  is  the  management  of  dataflow, i.e., timing.  Unless a
+       hardware terminal is interfaced into  a  terminal  concentrator  (which
        does flow control), it (or your application) must manage dataflow, pre-
        venting overruns.  The cheapest solution (no hardware cost) is for your
-       program to do this by pausing after operations that the  terminal  does
+       program  to  do this by pausing after operations that the terminal does
        slowly, such as clearing the display.
 
-       As  a  result,  many  terminal  descriptions (including the vt100) have
-       delay times embedded.  You may wish to use these descriptions, but  not
+       As a result, many terminal  descriptions  (including  the  vt100)  have
+       delay  times embedded.  You may wish to use these descriptions, but not
        want to pay the performance penalty.
 
-       Set  the  NCURSES_NO_PADDING  environment  variable  to disable all but
+       Set the NCURSES_NO_PADDING environment  variable  to  disable  all  but
        mandatory padding.  Mandatory padding is used as a part of special con-
        trol sequences such as flash.
 
@@ -935,44 +939,44 @@
 
           o   continued though 5.9 patch 20130126
 
-       ncurses  enabled  buffered output during terminal initialization.  This
+       ncurses enabled buffered output during terminal  initialization.   This
        was done (as in SVr4 curses) for performance reasons.  For testing pur-
-       poses,  both of ncurses and certain applications, this feature was made
+       poses, both of ncurses and certain applications, this feature was  made
        optional.   Setting  the  NCURSES_NO_SETBUF  variable  disabled  output
-       buffering,  leaving  the output in the original (usually line buffered)
+       buffering, leaving the output in the original (usually  line  buffered)
        mode.
 
-       In the current implementation, ncurses performs its own  buffering  and
-       does  not require this workaround.  It does not modify the buffering of
+       In  the  current implementation, ncurses performs its own buffering and
+       does not require this workaround.  It does not modify the buffering  of
        the standard output.
 
-       The reason for the change was to make the behavior for  interrupts  and
-       other  signals  more  robust.   One drawback is that certain nonconven-
-       tional programs would mix ordinary stdio calls with ncurses  calls  and
-       (usually)  work.  This is no longer possible since ncurses is not using
-       the buffered standard output but its  own  output  (to  the  same  file
+       The  reason  for the change was to make the behavior for interrupts and
+       other signals more robust.  One drawback  is  that  certain  nonconven-
+       tional  programs  would mix ordinary stdio calls with ncurses calls and
+       (usually) work.  This is no longer possible since ncurses is not  using
+       the  buffered  standard  output  but  its  own output (to the same file
        descriptor).  As a special case, the low-level calls such as putp still
        use the standard output.  But high-level curses calls do not.
 
 
 

NCURSES_NO_UTF8_ACS

-       During initialization, the ncurses library  checks  for  special  cases
+       During  initialization,  the  ncurses  library checks for special cases
        where VT100 line-drawing (and the corresponding alternate character set
-       capabilities) described in  the  terminfo  are  known  to  be  missing.
-       Specifically,  when running in a UTF-8 locale, the Linux console emula-
-       tor and the GNU screen program ignore these.  Ncurses checks  the  TERM
-       environment  variable  for  these.  For other special cases, you should
+       capabilities)  described  in  the  terminfo  are  known  to be missing.
+       Specifically, when running in a UTF-8 locale, the Linux console  emula-
+       tor  and  the GNU screen program ignore these.  Ncurses checks the TERM
+       environment variable for these.  For other special  cases,  you  should
        set this environment variable.  Doing this tells ncurses to use Unicode
-       values  which  correspond to the VT100 line-drawing glyphs.  That works
-       for the special cases cited, and is likely to work for terminal  emula-
+       values which correspond to the VT100 line-drawing glyphs.   That  works
+       for  the special cases cited, and is likely to work for terminal emula-
        tors.
 
        When setting this variable, you should set it to a nonzero value.  Set-
-       ting it to zero (or to a nonnumber)  disables  the  special  check  for
+       ting  it  to  zero  (or  to a nonnumber) disables the special check for
        "linux" and "screen".
 
-       As  an  alternative  to the environment variable, ncurses checks for an
-       extended terminfo capability U8.  This is a  numeric  capability  which
+       As an alternative to the environment variable, ncurses  checks  for  an
+       extended  terminfo  capability  U8.  This is a numeric capability which
        can be compiled using tic -x.  For example
 
           # linux console, if patched to provide working
@@ -984,99 +988,99 @@
           xterm-utf8|xterm relying on UTF-8 line-graphics,
                   U8#1, use=xterm,
 
-       The  name  "U8" is chosen to be two characters, to permit it to be used
+       The name "U8" is chosen to be two characters, to permit it to  be  used
        by applications that use ncurses' termcap interface.
 
 
 

NCURSES_TRACE

-       During  initialization,  the  ncurses  debugging  library  checks   the
-       NCURSES_TRACE  environment  variable.   If  it is defined, to a numeric
-       value, ncurses calls the trace function, using that value as the  argu-
+       During   initialization,  the  ncurses  debugging  library  checks  the
+       NCURSES_TRACE environment variable.  If it is  defined,  to  a  numeric
+       value,  ncurses calls the trace function, using that value as the argu-
        ment.
 
-       The  argument  values,  which  are defined in curses.h, provide several
-       types of information.  When running with traces enabled, your  applica-
+       The argument values, which are defined  in  curses.h,  provide  several
+       types  of information.  When running with traces enabled, your applica-
        tion will write the file trace to the current directory.
 
        See curs_trace(3x) for more information.
 
 
 

TERM

-       Denotes  your  terminal  type.   Each terminal type is distinct, though
+       Denotes your terminal type.  Each terminal  type  is  distinct,  though
        many are similar.
 
-       TERM is commonly set by terminal emulators to help applications find  a
+       TERM  is commonly set by terminal emulators to help applications find a
        workable terminal description.  Some of those choose a popular approxi-
-       mation, e.g., "ansi", "vt100", "xterm" rather than an exact  fit.   Not
-       infrequently,  your  application will have problems with that approach,
+       mation,  e.g.,  "ansi", "vt100", "xterm" rather than an exact fit.  Not
+       infrequently, your application will have problems with  that  approach,
        e.g., incorrect function-key definitions.
 
-       If you set TERM in your environment, it has no effect on the  operation
-       of  the  terminal  emulator.  It only affects the way applications work
-       within the terminal.  Likewise, as a general rule (xterm being  a  rare
-       exception),  terminal  emulators  which  allow you to specify TERM as a
-       parameter or configuration value do not change their behavior to  match
+       If  you set TERM in your environment, it has no effect on the operation
+       of the terminal emulator.  It only affects the  way  applications  work
+       within  the  terminal.  Likewise, as a general rule (xterm being a rare
+       exception), terminal emulators which allow you to  specify  TERM  as  a
+       parameter  or configuration value do not change their behavior to match
        that setting.
 
 
 

TERMCAP

-       If  the  ncurses  library  has  been  configured  with termcap support,
-       ncurses will check for a terminal's description in termcap form  if  it
+       If the ncurses  library  has  been  configured  with  termcap  support,
+       ncurses  will  check for a terminal's description in termcap form if it
        is not available in the terminfo database.
 
        The TERMCAP environment variable contains either a terminal description
        (with newlines stripped out), or a file name telling where the informa-
-       tion  denoted by the TERM environment variable exists.  In either case,
-       setting it directs ncurses to ignore the usual place for this  informa-
+       tion denoted by the TERM environment variable exists.  In either  case,
+       setting  it directs ncurses to ignore the usual place for this informa-
        tion, e.g., /etc/termcap.
 
 
 

TERMINFO

-       ncurses  can  be  configured  to read from multiple terminal databases.
-       The TERMINFO variable overrides the location for the  default  terminal
-       database.   Terminal  descriptions  (in  terminal format) are stored in
+       ncurses can be configured to read  from  multiple  terminal  databases.
+       The  TERMINFO  variable overrides the location for the default terminal
+       database.  Terminal descriptions (in terminal  format)  are  stored  in
        terminal databases:
 
        o   Normally these are stored in a directory tree, using subdirectories
            named by the first letter of the terminal names therein.
 
            This is the scheme used in System V, which legacy Unix systems use,
-           and the TERMINFO variable is used by curses applications  on  those
+           and  the  TERMINFO variable is used by curses applications on those
            systems to override the default location of the terminal database.
 
-       o   If  ncurses  is  built  to use hashed databases, then each entry in
+       o   If ncurses is built to use hashed databases,  then  each  entry  in
            this list may be the path of a hashed database file, e.g.,
 
-             /usr/share/terminfo.db
+               /usr/share/terminfo.db
 
            rather than
 
-             /usr/share/terminfo/
+               /usr/share/terminfo/
 
-           The hashed database uses less disk-space and  is  a  little  faster
-           than  the  directory  tree.   However, some applications assume the
-           existence of the directory tree, reading it  directly  rather  than
+           The  hashed  database  uses  less disk-space and is a little faster
+           than the directory tree.  However,  some  applications  assume  the
+           existence  of  the  directory tree, reading it directly rather than
            using the terminfo library calls.
 
-       o   If  ncurses  is  built  with  a  support  for reading termcap files
-           directly, then an entry in this list may be the path of  a  termcap
+       o   If ncurses is built  with  a  support  for  reading  termcap  files
+           directly,  then  an entry in this list may be the path of a termcap
            file.
 
        o   If the TERMINFO variable begins with "hex:" or "b64:", ncurses uses
-           the remainder of that variable as a compiled terminal  description.
+           the  remainder of that variable as a compiled terminal description.
            You might produce the base64 format using infocmp(1m):
 
-             TERMINFO="$(infocmp -0 -Q2 -q)"
-             export TERMINFO
+               TERMINFO="$(infocmp -0 -Q2 -q)"
+               export TERMINFO
 
-           The  compiled description is used if it corresponds to the terminal
+           The compiled description is used if it corresponds to the  terminal
            identified by the TERM variable.
 
-       Setting TERMINFO is the simplest, but not the only way to set  location
-       of  the default terminal database.  The complete list of database loca-
+       Setting  TERMINFO is the simplest, but not the only way to set location
+       of the default terminal database.  The complete list of database  loca-
        tions in order follows:
 
-          o   the last terminal database to which ncurses wrote,  if  any,  is
+          o   the  last  terminal  database to which ncurses wrote, if any, is
               searched first
 
           o   the location specified by the TERMINFO environment variable
@@ -1085,7 +1089,7 @@
 
           o   locations listed in the TERMINFO_DIRS environment variable
 
-          o   one  or  more  locations whose names are configured and compiled
+          o   one or more locations whose names are  configured  and  compiled
               into the ncurses library, i.e.,
 
              o   /usr/local/ncurses/share/terminfo:/usr/share/terminfo (corre-
@@ -1095,9 +1099,9 @@
 
 
 

TERMINFO_DIRS

-       Specifies  a  list  of  locations  to search for terminal descriptions.
-       Each location in the list is a terminal database as  described  in  the
-       section  on  the  TERMINFO  variable.   The list is separated by colons
+       Specifies a list of locations  to  search  for  terminal  descriptions.
+       Each  location  in  the list is a terminal database as described in the
+       section on the TERMINFO variable.  The  list  is  separated  by  colons
        (i.e., ":") on Unix, semicolons on OS/2 EMX.
 
        There is no corresponding feature in System V terminfo; it is an exten-
@@ -1105,66 +1109,87 @@
 
 
 

TERMPATH

-       If  TERMCAP  does not hold a file name then ncurses checks the TERMPATH
-       environment variable.  This is a list of filenames separated by  spaces
+       If TERMCAP does not hold a file name then ncurses checks  the  TERMPATH
+       environment  variable.  This is a list of filenames separated by spaces
        or colons (i.e., ":") on Unix, semicolons on OS/2 EMX.
 
-       If  the  TERMPATH environment variable is not set, ncurses looks in the
+       If the TERMPATH environment variable is not set, ncurses looks  in  the
        files
 
-         /etc/termcap, /usr/share/misc/termcap and $HOME/.termcap,
+           /etc/termcap, /usr/share/misc/termcap and $HOME/.termcap,
 
        in that order.
 
        The library may be configured to disregard the following variables when
-       the  current  user  is the superuser (root), or if the application uses
+       the current user is the superuser (root), or if  the  application  uses
        setuid or setgid permissions:
 
-         $TERMINFO, $TERMINFO_DIRS, $TERMPATH, as well as $HOME.
+           $TERMINFO, $TERMINFO_DIRS, $TERMPATH, as well as $HOME.
 
 
 

ALTERNATE CONFIGURATIONS

        Several different configurations are possible, depending on the config-
-       ure  script  options  used when building ncurses.  There are a few main
-       options whose effects are visible to the applications  developer  using
+       ure script options used when building ncurses.  There are  a  few  main
+       options  whose  effects are visible to the applications developer using
        ncurses:
 
        --disable-overwrite
             The standard include for ncurses is as noted in SYNOPSIS:
 
-              #include <curses.h>
+                #include <curses.h>
 
-            This  option  is  used to avoid filename conflicts when ncurses is
+            This option is used to avoid filename conflicts  when  ncurses  is
             not the main implementation of curses of the computer.  If ncurses
-            is  installed disabling overwrite, it puts its headers in a subdi-
+            is installed disabling overwrite, it puts its headers in a  subdi-
             rectory, e.g.,
 
-              #include <ncurses/curses.h>
+                #include <ncurses/curses.h>
 
-            It also omits a  symbolic  link  which  would  allow  you  to  use
+            It  also  omits  a  symbolic  link  which  would  allow you to use
             -lcurses to build executables.
 
        --enable-widec
-            The  configure  script  renames  the  library  and  (if the --dis-
-            able-overwrite option is used) puts the header files in a  differ-
+            The configure script  renames  the  library  and  (if  the  --dis-
+            able-overwrite  option is used) puts the header files in a differ-
             ent subdirectory.  All of the library names have a "w" appended to
             them, i.e., instead of
 
-              -lncurses
+                -lncurses
 
             you link with
 
-              -lncursesw
+                -lncursesw
+
+            You  must  also  enable  the wide-character features in the header
+            file when compiling for the  wide-character  library  to  use  the
+            extended  (wide-character)  functions.   The  symbol which enables
+            these features has changed since XSI Curses, Issue 4:
+
+            o   Originally, the wide-character  feature  required  the  symbol
+                _XOPEN_SOURCE_EXTENDED  but  that  was  only  valid  for  XPG4
+                (1996).
+
+            o   Later, that was deemed conflicting with _XOPEN_SOURCE  defined
+                to 500.
 
-            You must also define _XOPEN_SOURCE_EXTENDED when compiling for the
-            wide-character  library to use the extended (wide-character) func-
-            tions.  The curses.h file which is installed for the  wide-charac-
-            ter library is designed to be compatible with the normal library's
+            o   As  of  mid-2018,  none of the features in this implementation
+                require a _XOPEN_SOURCE feature greater  than  600.   However,
+                X/Open Curses, Issue 7 (2009) recommends defining it to 700.
+
+            o   Alternatively,   you   can  enable  the  feature  by  defining
+                NCURSES_WIDECHAR with the caveat that some other  header  file
+                than  curses.h  may require a specific value for _XOPEN_SOURCE
+                (or a system-specific symbol).
+
+            The curses.h  file  which  is  installed  for  the  wide-character
+            library  is  designed  to  be compatible with the normal library's
             header.  Only the size of the WINDOW structure differs,  and  very
-            few  applications  require more than a pointer to WINDOWs.  If the
-            headers  are  installed  allowing  overwrite,  the  wide-character
-            library's  headers should be installed last, to allow applications
-            to be built using either library from the same set of headers.
+            few applications require more than a pointer to WINDOWs.
+
+            If  the headers are installed allowing overwrite, the wide-charac-
+            ter library's headers should be installed last, to allow  applica-
+            tions  to be built using either library from the same set of head-
+            ers.
 
        --with-pthread
             The configure script renames the  library.   All  of  the  library
@@ -1205,6 +1230,7 @@
        terminfo(5) and related pages whose names begin  "curs_"  for  detailed
        routine descriptions.
        curs_variables(3x)
+       user_caps(5) for user-defined capabilities
 
 
 

EXTENSIONS

@@ -1222,7 +1248,7 @@
        The ncurses library includes facilities for responding to window resiz-
        ing events, e.g., when running in an xterm.  See the resizeterm(3x) and
        wresize(3x) manual pages for details.  In addition, the library may  be
-       configured with a SIGWINCH handler.
+       configured with a SIGWINCH handler.
 
        The  ncurses library extends the fixed set of function key capabilities
        of terminals by allowing the application designer to define  additional
@@ -1251,28 +1277,37 @@
        between  the XSI Curses and ncurses calls) are described in PORTABILITY
        sections of the library man pages.
 
+
+

Error checking

+       In many cases, X/Open Curses is vague about error conditions,  omitting
+       some of the SVr4 documentation.
+
        Unlike other implementations, this one checks parameters such as point-
-       ers  to WINDOW structures to ensure they are not null.  The main reason
-       for providing this behavior is to guard against programmer error.   The
-       standard  interface  does  not provide a way for the library to tell an
+       ers to WINDOW structures to ensure they are not null.  The main  reason
+       for  providing this behavior is to guard against programmer error.  The
+       standard interface does not provide a way for the library  to  tell  an
        application which of several possible errors were detected.  Relying on
        this (or some other) extension will adversely affect the portability of
        curses applications.
 
-       This implementation also contains several extensions:
+
+

Extensions versus portability

+       Most  of the extensions provided by ncurses have not been standardized.
+       Some  have  been  incorporated  into  other  implementations,  such  as
+       PDCurses or NetBSD curses.  Here are a few to consider:
 
        o   The routine has_key is not part of XPG4, nor is it present in SVr4.
            See the curs_getch(3x) manual page for details.
 
-       o   The  routine  slk_attr  is  not  part of XPG4, nor is it present in
+       o   The routine slk_attr is not part of XPG4,  nor  is  it  present  in
            SVr4.  See the curs_slk(3x) manual page for details.
 
-       o   The routines getmouse, mousemask,  ungetmouse,  mouseinterval,  and
-           wenclose  relating  to  mouse interfacing are not part of XPG4, nor
-           are they present in SVr4.  See the curs_mouse(3x) manual  page  for
+       o   The  routines  getmouse,  mousemask, ungetmouse, mouseinterval, and
+           wenclose relating to mouse interfacing are not part  of  XPG4,  nor
+           are  they  present in SVr4.  See the curs_mouse(3x) manual page for
            details.
 
-       o   The  routine  mcprint was not present in any previous curses imple-
+       o   The routine mcprint was not present in any previous  curses  imple-
            mentation.  See the curs_print(3x) manual page for details.
 
        o   The routine wresize is not part of XPG4, nor is it present in SVr4.
@@ -1282,28 +1317,118 @@
            tion programs.  See curs_opaque(3x) for the discussion of is_scrol-
            lok, etc.
 
-       o   This  implementation  can be configured to provide rudimentary sup-
-           port for multi-threaded  applications.   See  curs_threads(3x)  for
+       o   This implementation can be configured to provide  rudimentary  sup-
+           port  for  multi-threaded  applications.   See curs_threads(3x) for
            details.
 
-       o   This  implementation  can  also  be  configured to provide a set of
-           functions which improve the ability  to  manage  multiple  screens.
+       o   This implementation can also be configured  to  provide  a  set  of
+           functions  which  improve  the  ability to manage multiple screens.
            See curs_sp_funcs(3x) for details.
 
-       In  historic  curses  versions, delays embedded in the capabilities cr,
-       ind, cub1, ff and tab activated corresponding delay bits  in  the  UNIX
+
+

Padding differences

+       In historic curses versions, delays embedded in  the  capabilities  cr,
+       ind,  cub1,  ff  and tab activated corresponding delay bits in the UNIX
        tty driver.  In this implementation, all padding is done by sending NUL
-       bytes.  This method is slightly more expensive, but narrows the  inter-
-       face  to  the  UNIX  kernel  significantly  and increases the package's
+       bytes.   This method is slightly more expensive, but narrows the inter-
+       face to the UNIX  kernel  significantly  and  increases  the  package's
        portability correspondingly.
 
 
-

NOTES

-       The header file <curses.h>  automatically  includes  the  header  files
+

Header files

+       The  header  file  <curses.h>  automatically  includes the header files
        <stdio.h> and <unctrl.h>.
 
-       If  standard  output from a ncurses program is re-directed to something
-       which is not a tty, screen updates will be directed to standard  error.
+       X/Open Curses has more to say, but does not finish the story:
+
+           The inclusion of <curses.h> may make visible all symbols  from  the
+           headers <stdio.h>, <term.h>, <termios.h>, and <wchar.h>.
+
+       Here is a more complete story:
+
+       o   Starting   with  BSD  curses,  all  implementations  have  included
+           <stdio.h>.
+
+           BSD curses included <curses.h>  and  <unctrl.h>  from  an  internal
+           header "curses.ext" ("ext" was a short name for externs).
+
+           BSD  curses  used  <stdio.h> internally (for printw and scanw), but
+           nothing in <curses.h> itself relied upon <stdio.h>.
+
+       o   SVr2 curses added newterm(3x), which relies upon  <stdio.h>.   That
+           is, the function prototype uses FILE.
+
+           SVr4 curses added putwin and getwin, which also use <stdio.h>.
+
+           X/Open Curses documents all three of these functions.
+
+           SVr4  curses  and  X/Open  Curses  do  not require the developer to
+           include  <stdio.h>  before  including  <curses.h>.   Both  document
+           curses showing <curses.h> as the only required header.
+
+           As a result, standard <curses.h> will always include <stdio.h>.
+
+       o   X/Open  Curses is inconsistent with respect to SVr4 regarding <unc-
+           trl.h>.
+
+           As  noted  in  curs_util(3x),  ncurses  includes  <unctrl.h>   from
+           <curses.h> (like SVr4).
+
+       o   X/Open's comments about <term.h> and <termios.h> may refer to HP-UX
+           and AIX:
+
+           HP-UX curses includes <term.h> from <curses.h> to declare setupterm
+           in curses.h, but ncurses (and Solaris curses) do not.
+
+           AIX  curses includes <term.h> and <termios.h>.  Again, ncurses (and
+           Solaris curses) do not.
+
+       o   X/Open says that <curses.h> may include <term.h>, but there  is  no
+           requirement that it do that.
+
+           Some  programs  use  functions  declared  in  both  <curses.h>  and
+           <term.h>, and must include both headers in the same  module.   Very
+           old  versions  of  AIX  curses required including <curses.h> before
+           including <term.h>.
+
+           Because ncurses header files include the headers needed  to  define
+           datatypes used in the headers, ncurses header files can be included
+           in any order.  But for portability, you should  include  <curses.h>
+           before <term.h>.
+
+       o   X/Open  Curses  says  "may make visible" because including a header
+           file does not necessarily make all symbols in it visible (there are
+           ifdef's to consider).
+
+           For  instance,  in  ncurses <wchar.h> may be included if the proper
+           symbol is defined, and if ncurses is configured for  wide-character
+           support.   If the header is included, its symbols may be made visi-
+           ble.  That depends on the value used for _XOPEN_SOURCE feature test
+           macro.
+
+       o   X/Open  Curses  documents  one  required header, in a special case:
+           <stdarg.h>  before  <curses.h>  to  prototype  the  vw_printw   and
+           vw_scanw  functions  (as well as the obsolete the vwprintw and vws-
+           canw functions).  Each of those uses a va_list parameter.
+
+           The two obsolete functions were  introduced  in  SVr3.   The  other
+           functions  were  introduced  in  X/Open  Curses.   In between, SVr4
+           curses provided for  the  possibility  that  an  application  might
+           include either <varargs.h> or <stdarg.h>.  Initially, that was done
+           by using void* for the va_list parameter.  Later,  a  special  type
+           (defined  in <stdio.h>) was introduced, to allow for compiler type-
+           checking.  That special type is always available, because <stdio.h>
+           is always included by <curses.h>.
+
+           None of the X/Open Curses implementations require an application to
+           include <stdarg.h>  before  <curses.h>  because  they  either  have
+           allowed  for  a  special type, or (like ncurses) include <stdarg.h>
+           directly to provide a portable interface.
+
+
+

NOTES

+       If standard output from a ncurses program is re-directed  to  something
+       which  is not a tty, screen updates will be directed to standard error.
        This was an undocumented feature of AT&T System V Release 3 curses.
 
 
@@ -1358,7 +1483,14 @@
 
  • FILES
  • SEE ALSO
  • EXTENSIONS
  • -
  • PORTABILITY
  • +
  • PORTABILITY + +
  • NOTES
  • AUTHORS