The GNU Readline library provides a set of functions for use by applications that allow users to edit command lines as they are typed in. Both Emacs and vi editing modes are available. The Readline library includes additional functions to maintain a list of previously-entered command lines, to recall and perhaps reedit those lines, and perform csh-like history expansion on previous commands.

This function gives the user the default behaviour of TAB completion: completion on file names. If you do not want Readline to complete on filenames, you can change the binding of the TAB key with rl_bind_key().

int rl_bind_key (int key, rl_command_func_t *function);

rl_bind_key() takes two arguments: key is the character that you want to bind, and function is the address of the function to call when key is pressed. Binding TAB to rl_insert() makes TAB insert itself. rl_bind_key() returns non-zero if key is not a valid ASCII character code (between 0 and 255).

Thus, to disable the default TAB behavior, the following suffices:

rl_bind_key (‘\t’, rl_insert);

This code should be executed once at the start of your program; you might write a function called initialize_readline() which performs this and other desired initializations, such as installing custom completers.


GNU Readline Offical Site:

If you want to use GNU Readline library in your program:

* 1st, include <readline/readline.h> and <readline/history.h>
* 2nd, invoke readline function such as char *readline (const char *prompt); add_history (line);
 * 3rd, link source file with -lreadline -ltermcap arguments