.\"***************************************************************************
-.\" Copyright (c) 1998-2016,2017 Free Software Foundation, Inc. *
+.\" Copyright (c) 1998-2017,2018 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 *
.\" authorization. *
.\"***************************************************************************
.\"
-.\" $Id: term.5,v 1.27 2017/12/16 21:27:20 tom Exp $
+.\" $Id: term.5,v 1.28 2018/03/31 22:41:29 tom Exp $
.TH term 5
.ie \n(.g .ds `` \(lq
.el .ds `` ``
.SH DESCRIPTION
.SS STORAGE LOCATION
Compiled terminfo descriptions are placed under the directory \fB\*d\fP.
-Two configurations are supported (when building the ncurses libraries):
+Two configurations are supported (when building the \fBncurses\fP libraries):
.TP 5
.B directory tree
A two-level scheme is used to avoid a linear search
and records containing only aliases pointing to the primary name.
.IP
If built to write hashed databases,
-ncurses can still read terminfo databases organized as a directory tree,
+\fBncurses\fP can still read terminfo databases organized as a directory tree,
but cannot write entries into the directory tree.
It can write (or rewrite) entries in the hashed database.
.IP
-ncurses distinguishes the two cases in the TERMINFO and TERMINFO_DIRS
+\fBncurses\fP distinguishes the two cases in the TERMINFO and TERMINFO_DIRS
environment variable by assuming a directory tree for entries that
correspond to an existing directory,
and hashed database otherwise.
and the second byte contains the most significant 8 bits.
(Thus, the value represented is 256*second+first.)
The value \-1 is represented by the two bytes 0377, 0377; other negative
-values are illegal. This value generally
+values are illegal.
+This value generally
means that the corresponding capability is missing from this terminal.
Note that this format corresponds to the hardware of the \s-1VAX\s+1
and \s-1PDP\s+1-11 (that is, little-endian machines).
the same binary format is used in all modern UNIX systems.
Each system uses a predefined set of boolean, number or string capabilities.
.PP
-The ncurses libraries and applications support extended terminfo binary format,
-allowing users to define capabilities which are loaded at runtime. This
+The \fBncurses\fP libraries and applications support extended terminfo binary format,
+allowing users to define capabilities which are loaded at runtime.
+This
extension is made possible by using the fact that the other implementations
stop reading the terminfo data when they have reached the end of the size given
in the header.
-ncurses checks the size, and if it exceeds that due to the predefined data,
+\fBncurses\fP checks the size,
+and if it exceeds that due to the predefined data,
continues to parse according to its own scheme.
.PP
First, it reads the extended header (5 short integers):
count of extended string capabilities
.TP 5
(4)
-size of the extended string table in bytes.
+count of the items in extended string table
.TP 5
(5)
-last offset of the extended string table in bytes.
+size of the extended string table in bytes
.RE
.PP
-Using the counts and sizes, ncurses allocates arrays and reads data
+The count- and size-values for the extended string table
+include the extended capability \fInames\fP as well as
+extended capability \fIvalues\fP.
+.PP
+Using the counts and sizes, \fBncurses\fP allocates arrays and reads data
for the extended capabilities in the same order as the header information.
.PP
The extended string table contains values for string capabilities.
.SS EXTENDED NUMBER FORMAT
.PP
On occasion, 16-bit signed integers are not large enough.
-With ncurses 6.1, a new format is introduced by making a few changes
+With \fBncurses\fP 6.1, a new format was introduced by making a few changes
to the legacy format:
.bP
a different magic number (0542)
.PP
Despite the consistent use of little-endian for numbers and the otherwise
self-describing format, it is not wise to count on portability of binary
-terminfo entries between commercial UNIX versions. The problem is that there
+terminfo entries between commercial UNIX versions.
+The problem is that there
are at least three versions of terminfo (under HP\-UX, AIX, and OSF/1) which
diverged from System V terminfo after SVr1, and have added extension
capabilities to the string table that (in the binary format) collide with
-System V and XSI Curses extensions. See \fBterminfo\fR(\*n) for detailed
+System V and XSI Curses extensions.
+See \fBterminfo\fR(\*n) for detailed
discussion of terminfo source compatibility issues.
.PP
Direct access to the \fBTERMTYPE\fP structure is provided for legacy
their names.
If the underlying filesystem ignores the difference between
uppercase and lowercase,
-ncurses represents the \*(``first character\*('' of the terminal name used as
+\fBncurses\fP represents the \*(``first character\*('' of the terminal name used as
the intermediate level of a directory tree in (two-character) hexadecimal form.
.SH EXAMPLE
As an example, here is a description for the Lear-Siegler
projects / ncurses.git / blobdiff