ncurses 5.9 - patch 20130518

[ncurses.git] / man / ncurses.3x

diff --git a/man/ncurses.3x b/man/ncurses.3x
index 9dcdcd940a4c519afdf348a8916a2aacccb7aea7..c5fdc87471fb3ccd09bdd5b205fa350b064d0fc7 100644 (file)
--- a/man/ncurses.3x
+++ b/man/ncurses.3x
@@ -1,6 +1,6 @@
 '\" t
 .\"***************************************************************************
 '\" t
 .\"***************************************************************************

-.\" Copyright (c) 1998-2009,2010 Free Software Foundation, Inc.              *
+.\" Copyright (c) 1998-2012,2013 Free Software Foundation, Inc.              *

 .\"                                                                          *
 .\" Permission is hereby granted, free of charge, to any person obtaining a  *
 .\" copy of this software and associated documentation files (the            *
 .\"                                                                          *
 .\" Permission is hereby granted, free of charge, to any person obtaining a  *
 .\" copy of this software and associated documentation files (the            *


@@ -27,7 +27,7 @@
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"

-.\" $Id: ncurses.3x,v 1.101 2010/12/04 18:38:55 tom Exp $
+.\" $Id: ncurses.3x,v 1.111 2013/03/02 22:15:25 tom Exp $

 .hy 0
 .TH ncurses 3X ""
 .de bP
 .hy 0
 .TH ncurses 3X ""
 .de bP


@@ -55,8 +55,10 @@ and XPG4 (X/Open Portability Guide) curses (also known as XSI curses).
 XSI stands for X/Open System Interfaces Extension.
 The \fBncurses\fR library is freely redistributable in source form.
 Differences from the SVr4
 XSI stands for X/Open System Interfaces Extension.
 The \fBncurses\fR library is freely redistributable in source form.
 Differences from the SVr4

-curses are summarized under the \fBEXTENSIONS\fP and \fBPORTABILITY\fP sections below and
-described in detail in the respective \fBEXTENSIONS\fP, \fBPORTABILITY\fP and \fBBUGS\fP sections
+curses are summarized under the
+\fBEXTENSIONS\fP and \fBPORTABILITY\fP sections below and
+described in detail in the respective
+\fBEXTENSIONS\fP, \fBPORTABILITY\fP and \fBBUGS\fP sections

 of individual man pages.
 .PP
 The \fBncurses\fR library also provides many useful extensions,
 of individual man pages.
 .PP
 The \fBncurses\fR library also provides many useful extensions,


@@ -108,9 +110,9 @@ Most programs would additionally use the sequence:
 .sp
 Before a \fBcurses\fR program is run, the tab stops of the terminal
 should be set and its initialization strings, if defined, must be output.
 .sp
 Before a \fBcurses\fR program is run, the tab stops of the terminal
 should be set and its initialization strings, if defined, must be output.

-This can be done by executing the \fBtput init\fR command
+This can be done by executing the \fB@TPUT@ init\fR command

 after the shell environment variable \fBTERM\fR has been exported.
 after the shell environment variable \fBTERM\fR has been exported.

-\fBtset(1)\fR is usually responsible for doing this.
+\fB@TSET@(1)\fR is usually responsible for doing this.

 [See \fBterminfo\fR(\*n) for further details.]
 .PP
 The \fBncurses\fR library permits manipulation of data structures,
 [See \fBterminfo\fR(\*n) for further details.]
 .PP
 The \fBncurses\fR library permits manipulation of data structures,


@@ -637,6 +639,7 @@ use_default_colors/\fBdefault_colors\fR(3X)*
 use_env/\fBcurs_util\fR(3X)
 use_extended_names/\fBcurs_extend\fR(3X)*
 use_legacy_coding/\fBlegacy_coding\fR(3X)*
 use_env/\fBcurs_util\fR(3X)
 use_extended_names/\fBcurs_extend\fR(3X)*
 use_legacy_coding/\fBlegacy_coding\fR(3X)*

+use_tioctl/\fBcurs_util\fR(3X)

 vid_attr/\fBcurs_terminfo\fR(3X)
 vid_puts/\fBcurs_terminfo\fR(3X)
 vidattr/\fBcurs_terminfo\fR(3X)
 vid_attr/\fBcurs_terminfo\fR(3X)
 vid_puts/\fBcurs_terminfo\fR(3X)
 vidattr/\fBcurs_terminfo\fR(3X)


@@ -734,9 +737,16 @@ Routines that return an integer return \fBERR\fR upon failure and an
 integer value other than \fBERR\fR upon successful completion, unless
 otherwise noted in the routine descriptions.
 .PP
 integer value other than \fBERR\fR upon successful completion, unless
 otherwise noted in the routine descriptions.
 .PP

+As a general rule, routines check for null pointers passed as parameters,
+and handle this as an error.
+.PP

 All macros return the value of the \fBw\fR version, except \fBsetscrreg\fR,
 \fBwsetscrreg\fR, \fBgetyx\fR, \fBgetbegyx\fR, and \fBgetmaxyx\fR.
 All macros return the value of the \fBw\fR version, except \fBsetscrreg\fR,
 \fBwsetscrreg\fR, \fBgetyx\fR, \fBgetbegyx\fR, and \fBgetmaxyx\fR.

-The return values of \fBsetscrreg\fR, \fBwsetscrreg\fR, \fBgetyx\fR, \fBgetbegyx\fR, and
+The return values of
+\fBsetscrreg\fR,
+\fBwsetscrreg\fR,
+\fBgetyx\fR,
+\fBgetbegyx\fR, and

 \fBgetmaxyx\fR are undefined (i.e., these should not be used as the
 right-hand side of assignment statements).
 .PP
 \fBgetmaxyx\fR are undefined (i.e., these should not be used as the
 right-hand side of assignment statements).
 .PP


@@ -747,9 +757,9 @@ runtime behavior of the \fBncurses\fR library.
 The most important ones have been already discussed in detail.
 .TP 5
 BAUDRATE
 The most important ones have been already discussed in detail.
 .TP 5
 BAUDRATE

-The debugging library checks this environment symbol when the application
+The debugging library checks this environment variable when the application

 has redirected output to a file.
 has redirected output to a file.

-The symbol's numeric value is used for the baudrate.
+The variable's numeric value is used for the baudrate.

 If no value is found, \fBncurses\fR uses 9600.
 This allows testers to construct repeatable test-cases
 that take into account costs that depend on baudrate.
 If no value is found, \fBncurses\fR uses 9600.
 This allows testers to construct repeatable test-cases
 that take into account costs that depend on baudrate.


@@ -757,7 +767,7 @@ that take into account costs that depend on baudrate.
 CC
 When set, change occurrences of the command_character
 (i.e., the \fBcmdch\fP capability)
 CC
 When set, change occurrences of the command_character
 (i.e., the \fBcmdch\fP capability)

-of the loaded terminfo entries to the value of this symbol.
+of the loaded terminfo entries to the value of this variable.

 Very few terminfo entries provide this feature.
 .IP
 Because this name is also used in development environments to represent
 Very few terminfo entries provide this feature.
 .IP
 Because this name is also used in development environments to represent


@@ -786,7 +796,9 @@ For best results, \fBlines\fR and \fBcols\fR should not be specified in
 a terminal description for terminals which are run as emulations.
 .IP
 Use the \fBuse_env\fR function to disable all use of external environment
 a terminal description for terminals which are run as emulations.
 .IP
 Use the \fBuse_env\fR function to disable all use of external environment

-(including system calls) to determine the screen size.
+(but not including system calls) to determine the screen size.
+Use the \fBuse_tioctl\fR function to update \fBCOLUMNS\fP or \fBLINES\fP
+to match the screen size obtained from system calls or the terminal database.

 .TP 5
 ESCDELAY
 Specifies the total time, in milliseconds, for which ncurses will
 .TP 5
 ESCDELAY
 Specifies the total time, in milliseconds, for which ncurses will


@@ -837,8 +849,8 @@ platforms:
 .br
 3 = middle.
 .sp
 .br
 3 = middle.
 .sp

-This symbol lets you customize the mouse.
-The symbol must be three numeric digits 1\-3 in any order, e.g., 123 or 321.
+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 specified, \fBncurses\fR uses 132.
 .TP 5
 NCURSES_ASSUMED_COLORS
 If it is not specified, \fBncurses\fR uses 132.
 .TP 5
 NCURSES_ASSUMED_COLORS


@@ -899,19 +911,44 @@ have delay times embedded.
 You may wish to use these descriptions,
 but not want to pay the performance penalty.
 .IP
 You may wish to use these descriptions,
 but not want to pay the performance penalty.
 .IP

-Set the NCURSES_NO_PADDING symbol to disable all but mandatory
+Set the NCURSES_NO_PADDING environment variable to disable all but mandatory

 padding.
 Mandatory padding is used as a part of special control
 sequences such as \fIflash\fR.
 .TP 5
 NCURSES_NO_SETBUF
 padding.
 Mandatory padding is used as a part of special control
 sequences such as \fIflash\fR.
 .TP 5
 NCURSES_NO_SETBUF

-Normally \fBncurses\fR enables buffered output during terminal initialization.
-This is done (as in SVr4 curses) for performance reasons.
+This setting is obsolete.
+Before changes
+.RS
+.bP
+started with 5.9 patch 20120825 
+and
+.bP
+continued
+though 5.9 patch 20130126
+.RE
+.IP
+\fBncurses\fR enabled buffered output during terminal initialization.
+This was done (as in SVr4 curses) for performance reasons.

 For testing purposes, both of \fBncurses\fR and certain applications,
 For testing purposes, both of \fBncurses\fR and certain applications,

-this feature is made optional.
+this feature was made optional.

 Setting the NCURSES_NO_SETBUF variable
 Setting the NCURSES_NO_SETBUF variable

-disables output buffering, leaving the output in the original (usually
+disabled output buffering, leaving the output in the original (usually

 line buffered) mode.
 line buffered) mode.

+.IP
+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.
+.IP
+The reason for the change was to make the behavior for interrupts and
+other signals more robust.
+One drawback is that certain nonconventional 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 \fBputp\fP still use the
+standard output.
+But high-level curses calls do not.

 .TP 5
 NCURSES_NO_UTF8_ACS
 During initialization, the \fBncurses\fR library
 .TP 5
 NCURSES_NO_UTF8_ACS
 During initialization, the \fBncurses\fR library


@@ -930,10 +967,34 @@ and is likely to work for terminal emulators.
 When setting this variable, you should set it to a nonzero value.
 Setting it to zero (or to a nonnumber)
 disables the special check for "linux" and "screen".
 When setting this variable, you should set it to a nonzero value.
 Setting it to zero (or to a nonnumber)
 disables the special check for "linux" and "screen".

+.IP
+As an alternative to the environment variable,
+ncurses checks for an extended terminfo capability \fBU8\fP.
+This is a numeric capability which can be compiled using \fB@TIC@\ \-x\fP.
+For example
+.RS 5
+.ft CW
+.sp
+.nf
+# linux console, if patched to provide working
+# VT100 shift-in/shift-out, with corresponding font.
+linux-vt100|linux console with VT100 line-graphics,
+        U8#0, use=linux,
+.sp
+# uxterm with vt100Graphics resource set to false
+xterm-utf8|xterm relying on UTF-8 line-graphics,
+        U8#1, use=xterm,
+.fi
+.ft
+.RE
+.IP
+The name "U8" is chosen to be two characters,
+to permit it to be used by applications that use ncurses'
+termcap interface.

 .TP 5
 NCURSES_TRACE
 During initialization, the \fBncurses\fR debugging library
 .TP 5
 NCURSES_TRACE
 During initialization, the \fBncurses\fR debugging library

-checks the NCURSES_TRACE symbol.
+checks the NCURSES_TRACE environment variable.

 If it is defined, to a numeric value, \fBncurses\fR calls the \fBtrace\fR
 function, using that value as the argument.
 .IP
 If it is defined, to a numeric value, \fBncurses\fR calls the \fBtrace\fR
 function, using that value as the argument.
 .IP


@@ -951,9 +1012,10 @@ If the \fBncurses\fR library has been configured with \fItermcap\fR
 support, \fBncurses\fR will check for a terminal's description in
 termcap form if it is not available in the terminfo database.
 .IP
 support, \fBncurses\fR will check for a terminal's description in
 termcap form if it is not available in the terminfo database.
 .IP

-The TERMCAP symbol contains either a terminal description (with
+The TERMCAP environment variable contains either a terminal description (with

 newlines stripped out),
 newlines stripped out),

-or a file name telling where the information denoted by the TERM symbol exists.
+or a file name telling where the information denoted by
+the TERM environment variable exists.

 In either case, setting it directs \fBncurses\fR to ignore
 the usual place for this information, e.g., /etc/termcap.
 .TP 5
 In either case, setting it directs \fBncurses\fR to ignore
 the usual place for this information, e.g., /etc/termcap.
 .TP 5


@@ -966,33 +1028,51 @@ The complete list of directories in order follows:
 .bP
 the last directory to which \fBncurses\fR wrote, if any, is searched first
 .bP
 .bP
 the last directory to which \fBncurses\fR wrote, if any, is searched first
 .bP

-the directory specified by the TERMINFO symbol
+the directory specified by the TERMINFO environment variable

 .bP
 $HOME/.terminfo
 .bP
 .bP
 $HOME/.terminfo
 .bP

-directories listed in the TERMINFO_DIRS symbol
+directories listed in the TERMINFO_DIRS environment variable

 .bP
 one or more directories whose names are configured and compiled into the
 .bP
 one or more directories whose names are configured and compiled into the

-ncurses library, e.g.,
-@TERMINFO@
+ncurses library, i.e.,
+.RS
+.bP
+@TERMINFO_DIRS@ (corresponding to the TERMINFO_DIRS variable)
+.bP
+@TERMINFO@ (corresponding to the TERMINFO variable)
+.RE

 .RE
 .TP 5
 TERMINFO_DIRS
 Specifies a list of directories to search for terminal descriptions.
 The list is separated by colons (i.e., ":") on Unix, semicolons on OS/2 EMX.
 .RE
 .TP 5
 TERMINFO_DIRS
 Specifies a list of directories to search for terminal descriptions.
 The list is separated by colons (i.e., ":") on Unix, semicolons on OS/2 EMX.

-All of the terminal descriptions are in terminfo form, which makes
-a subdirectory named for the first letter of the terminal names therein.
+.IP
+All of the terminal descriptions are in terminfo form.
+Normally these are stored in a directory tree,
+using subdirectories named by the first letter of the terminal names therein.
+.IP
+If \fBncurses\fP is built with a hashed database,
+then each entry in this list can also be the path of the corresponding
+database file.
+.IP
+If \fBncurses\fP is built with a support for reading termcap files
+directly, then an entry in this list may be the path of a termcap file.

 .TP 5
 TERMPATH
 If TERMCAP does not hold a file name then \fBncurses\fR checks
 .TP 5
 TERMPATH
 If TERMCAP does not hold a file name then \fBncurses\fR checks

-the TERMPATH symbol.
-This is a list of filenames separated by spaces or colons (i.e., ":") on Unix, semicolons on OS/2 EMX.
-If the TERMPATH symbol is not set, \fBncurses\fR looks in the files
+the TERMPATH environment variable.
+This is a list of filenames separated by spaces or colons (i.e., ":") on Unix,
+semicolons on OS/2 EMX.
+.IP
+If the TERMPATH environment variable is not set,
+\fBncurses\fR looks in the files

 /etc/termcap, /usr/share/misc/termcap and $HOME/.termcap, in that order.
 .PP
 The library may be configured to disregard the following variables when the
 current user is the superuser (root), or if the application uses setuid or
 setgid permissions:
 /etc/termcap, /usr/share/misc/termcap and $HOME/.termcap, in that order.
 .PP
 The library may be configured to disregard the following variables when the
 current user is the superuser (root), or if the application uses setuid or
 setgid permissions:

+.IP

 $TERMINFO, $TERMINFO_DIRS, $TERMPATH, as well as $HOME.
 .SH ALTERNATE CONFIGURATIONS
 Several different configurations are possible,
 $TERMINFO, $TERMINFO_DIRS, $TERMPATH, as well as $HOME.
 .SH ALTERNATE CONFIGURATIONS
 Several different configurations are possible,


@@ -1020,8 +1100,9 @@ It also omits a symbolic link which would allow you to use \fB\-lcurses\fP
 to build executables.
 .TP 5
 \-\-enable\-widec
 to build executables.
 .TP 5
 \-\-enable\-widec

-The configure script renames the library and (if the \fB\-\-disable\-overwrite\fP
-option is used) puts the header files in a different subdirectory.
+The configure script renames the library and
+(if the \fB\-\-disable\-overwrite\fP option is used)
+puts the header files in a different subdirectory.

 All of the library names have a "w" appended to them,
 i.e., instead of
 .RS
 All of the library names have a "w" appended to them,
 i.e., instead of
 .RS


@@ -1071,8 +1152,8 @@ directory containing initialization files for the terminal capability database
 @TERMINFO@
 terminal capability database
 .SH SEE ALSO
 @TERMINFO@
 terminal capability database
 .SH SEE ALSO

-\fBterminfo\fR(\*n) and related pages whose names begin "curs_" for detailed routine
-descriptions.
+\fBterminfo\fR(\*n) and related pages whose names begin
+"curs_" for detailed routine descriptions.

 .br
 \fBcurs_variables\fR(3X) 
 .SH EXTENSIONS
 .br
 \fBcurs_variables\fR(3X) 
 .SH EXTENSIONS


@@ -1122,6 +1203,15 @@ A small number of local differences (that is, individual differences between
 the XSI Curses and \fBncurses\fR calls) are described in \fBPORTABILITY\fR
 sections of the library man pages.
 .PP
 the XSI Curses and \fBncurses\fR calls) are described in \fBPORTABILITY\fR
 sections of the library man pages.
 .PP

+Unlike other implementations, this one checks parameters such as pointers
+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.
+.PP

 This implementation also contains several extensions:
 .bP
 The routine \fBhas_key\fR is not part of XPG4, nor is it present in SVr4.
 This implementation also contains several extensions:
 .bP
 The routine \fBhas_key\fR is not part of XPG4, nor is it present in SVr4.