Chapter 3. Buffers used by Emacs Photo Database

Whenever you run commands which create output (as opposed to status messages which are displayed in the echo area), two windows may receive data. The *photo-output* buffer displays the command results proper, e.g. the print information. The *photo-messages* buffer receives warnings and error messages which database clients send to stderr. You can conveniently display the *photo-messages* buffer by running M-xphoto-show-messages after a command failed with an error message.


If you want to preserve search results displayed in the *photo-output* buffer for later use, simply rename the buffer: M-xrename-buffer newname. This temporary buffer is not associated with a file, although you can of course write it to a file using C-xC-w. Your next query will generate another buffer called *photo-output*. You can repeat this process any number of times to preserve an unlimited number of query results.

Commands that require additional data will prompt for these in the minibuffer. You can use the minibuffer history to recover any previously used input. In most cases you can also use minibuffer completion (tab or space key) to fill in the remainder of an argument or to choose between alternatives.

Emacs Photo Database provides three forms for data entry, see the commands Create Film, Create Negative, and Create Print. These forms are displayed in buffers named *photo-film*, *photo-negative*, and *photo-print*, respectively (they are also used to edit and update existing data). After filling in the forms, the commands Add Item and Update Item send the data to the database. You can edit the forms over and over again, keeping any invariant information, and thus use the forms to create additional datasets.