GNU Readline
GNU readline is a software library created and maintained by the GNU project. It is licensed under the GPL, and used in projects such as bash. It provides line-editing capabilities. The current version is 5.2.1. Newer features include multibyte (Unicode) character support.
For instance, in a readline-enabled application, pressing ctrl-b moves the cursor back one space, ctrl-f moves the cursor forward one space, and ctrl-r searches the command history. These key bindings (which are the default, although bindings like vi's are optional) are taken from one of GNU's earliest and most popular projects, the text editor Emacs. Readline supports a variety of basic features, including a kill ring (a more flexible version of a copy/paste clipboard) and tab completion. As a cross-platform library, readline allows applications on various systems to exhibit identical line-editing behavior.
Criticism
There are several bugs and limitations, making readline difficult to use by third party applications. Many features don't work as documented (for example, local echoing, which cannot be disabled), and removing key bindings is not possible. Its own manual page says, "It's too big and too slow."
While readline is a cross-platform library, many platforms do not include readline as part of the default system. Compiling and installing readline, as well as linking it properly to third party programs, can be a difficult process for many users.
See also
External links
- GNU readline homepage
- The Tecla command-line editing library - readline replacement with an MIT-style licence
- Editline Library (libedit) - readline replacement with a BSD-style licence