A few commands are interactive commands, for which the user must reply to a question. From menus, these commands display a dialog box with an input field string, an Ok button and a Cancel button. The input field string is called a mini-buffer.
Some commands are available in the mini-buffer to edit a line of text:
Two of them, Ctrl-p and Tab in the mini-buffer context, do not have the same function as in default mode.
Tab provides an expansion mechanism for file names. The beginning of a filename being entered in the mini-buffer, Tab key will complete it. However, if several filenames match the current pattern, the Message box is displayed with the possible choices. Note: the tilde character is expanded to the homedir path of the user.
In the same way, Tab provides an expansion mechanism for Smac names during an eval expression command. Smac names can be functions or variables names.If the expansion is not possible, a bell rings.
Ctrl-p restores the last string entered in the mini-buffer. This is useful when you make a mistake.
Cut and paste facilities (see §2.4 page 
) can be used in the
mini-buffer (one line only). The mini-buffer is shared by all buffers
of a session and is used in dialog-boxes, file-selectors and
control-panels.