Web Directory: php manual, ref.readline.php
GNU Readline

LXXXIX. GNU Readline


The readline() functions implement an interface to the GNU Readline library. These are functions that provide editable command lines. An example being the way Bash allows you to use the arrow keys to insert characters or scroll through command history. Because of the interactive nature of this library, it will be of little use for writing Web applications, but may be useful when writing scripts meant using PHP from the command line.

Note: This extension is not available on Windows platforms.


To use the readline functions, you need to install libreadline. You can find libreadline on the home page of the GNU Readline project, at http://cnswww.cns.cwru.edu/~chet/readline/rltop.php. It's maintained by Chet Ramey, who's also the author of Bash.

You can also use this functions with the libedit library, a non-GPL replacement for the readline library. The libedit library is BSD licensed and available for download from http://sourceforge.net/projects/libedit/.


To use this functions you must compile the CGI or CLI version of PHP with readline support. You need to configure PHP --with-readline[=DIR]. In order you want to use the libedit readline replacement, configure PHP --with-libedit[=DIR].

Runtime Configuration

This extension has no configuration directives defined in php.ini.

Resource Types

This extension has no resource types defined.

Predefined Constants

This extension has no constants defined.

Table of Contents
readline_add_history -- Adds a line to the history
readline_clear_history -- Clears the history
readline_completion_function -- Registers a completion function
readline_info -- Gets/sets various internal readline variables
readline_list_history -- Lists the history
readline_read_history -- Reads the history
readline_write_history -- Writes the history
readline -- Reads a line