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 to be run from a shell. The home page of the GNU Readline project is &url.readline;. It's maintained by Chet Ramey, who's also the author of Bash. readline Reads a line string readline string prompt This function returns a single string from the user. You may specify a string with which to prompt the user. The line returned has the ending newline removed. You must add this line to the history yourself using readline_add_history. readline_add_history Adds a line to the history void readline_add_history string line This function adds a line to the command line history. readline_clear_history Clears the history bool readline_clear_history This function clears the entire command line history. readline_completion_function Registers a completion function bool readline_completion_function string line This function registers a completion function. You must supply the name of an existing function which accepts a partial command line and returns an array of possible matches. This is the same kind of functionality you'd get if you hit your tab key while using Bash. readline_info Gets/sets various internal readline variables mixed readline_info string varname string newvalue If called with no parameters, this function returns an array of values for all the setting readline uses. The elements will be indexed by the following values: done, end, erase_empty_line, library_version, line_buffer, mark, pending_input, point, prompt, readline_name, and terminal_name. If called with one parameter, the value of that setting is returned. If called with two parameters, the setting will be changed to the given value. readline_list_history Lists the history array readline_list_history This function returns an array of the entire command line history. The elements are indexed by integers starting at zero. readline_read_history Reads the history bool readline_read_history string filename This function reads a command history from a file. readline_write_history Writes the history bool readline_write_history string filename This function writes the command history to a file.