Keyboard and mouse support

Automatic function key downloading

FMLI applications rely heavily on the use of function keys <F1> through <F8>. Because these keys are not available on some terminals or are not assigned default escape sequences that curses can use, FMLI provides alternative keystroke sequences, <CTRL-f> <1> through <CTRL-f> <8> respectively, whose use is equivalent to that of function keys. Some terminals, such as the AT&T 5620 and 630 terminals, as defined in their oldterminfo(4) entries, do not assign default escape sequences to these function keys, but can download strings into them. FMLI will automatically download the alternative keystroke sequences if either of the following is true:

the environment variable LOADPFK is set to yes, true, or the null string;
the user chooses FMLI function key downloading at a prompt given during initialization of the application. This prompt is not given if LOADPFK is set to any value.

In either case, the alternative sequences replace any previously defined strings for the function keys. You can, however, restore the previously defined strings if you have taken the precaution of storing them as an executable shell script. Such a script might use the tput utility as follows:

   tput pfx 1 'string-for-function-key-1'
   tput pfx 2 'string-for-function-key-2'
   tput pfx 3 'string-for-function-key-3'
   tput pfx 4 'string-for-function-key-4'
   tput pfx 5 'string-for-function-key-5'
   tput pfx 6 'string-for-function-key-6'
   tput pfx 7 'string-for-function-key-7'
   tput pfx 8 'string-for-function-key-8'

If you execute this script after exiting from an FMLI application, the stored function key definitions will be downloaded.

An FMLI application will execute this script automatically if it is named .restorePFKs. FMLI looks for a file named .restorePFKs first in the current directory, then in $HOME. If it finds such a file, the FMLI application displays the message

   Running the shell script in filename


   to restore function key settings

where filename is either .restorePFKs or $HOME/.restorePFKs.

NOTE: The tput utility must be UNIX System V Release 4 or later.

Referencing a terminfo entry for the AT&T 5620 terminal from a terminfo database older than UNIX System V Release 4 will cause the alternative keystroke sequences to be incorrectly downloaded. Not all the alternative sequences will be downloaded, and garbage may be output to the screen. This can occur if a user maintains a private variant of the terminfo entry. Such a user should not choose function key downloading.