Ncurses

As the new version, ncurses is a free and open-source software emulation of the System V Release 4.0 (SVr4) curses, which was an enhancement over the discontinued 4.4 BSD curses. The success of the BSD curses library prompted Bell Labs to release an enhanced curses library in their System V Release 2 Unix systems. This library was more powerful and instead of using termcap, it used terminfo. However, due to AT&T's policy regarding the distribution of source code, the improved curses library was not widely adopted in the BSD community. ncurses The pcurses library was further improved when Zeyd Ben-Halim took over the development effort in late 1991. The new library was released as ncurses in November 1993, with version 1.8.1 as the first major release. Subsequent work, through version 1.8.8 (M1995), was driven by Eric S. Raymond, who added the form and menu libraries written by Juergen Pfeifer. Since 1996, it has been maintained by Thomas E. Dickey. However, a few areas are problematic, such as handling terminal resizing, since no counterpart exists in the old curses. ==Terminal database==

ncurses can use either terminfo (with extensible data) or termcap. Other implementations of curses generally use terminfo; a minority use termcap. Few (mytinfo was an older exception) use both. ==License==

ncurses is a part of the GNU Project, but is not distributed under the GNU General Public License (GPL) or GNU Lesser General Public License (LGPL). Instead, it is distributed under a permissive free software licence: the MIT License. This is due to the agreement made with the Free Software Foundation at the time the developers assigned their copyright. When the agreement was made to pass on the rights to the FSF, there was a clause that stated: The Foundation promises that all distribution of the Package, or of any work "based on the Package", that takes place under the control of the Foundation or its agents or assignees, shall be on terms that explicitly and perpetually permit anyone possessing a copy of the work to which the terms apply, and possessing accurate notice of these terms, to redistribute copies of the work to anyone on the same terms. According to the maintainer Thomas E. Dickey, this precludes relicensing to the GPL in any version, since it would place restrictions on the programs that will be able to link to the libraries. ==Programs using ncurses==

Hundreds of programs use ncurses. Some, such as GNU Screen and w3m, use only the termcap interface and perform screen management themselves. Others, such as GNU Midnight Commander and Yet another Setup Tool (YaST), use the curses programming interface. ==See also==