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enhance(1)		    General Commands Manual		    enhance(1)

       enhance	- A program that adds command-line editing to third party pro-

       enhance command [ argument ... ]

       The enhance program provides enhanced command-line  editing  facilities
       to  users  of  third  party applications, to which one doesn't have any
       source code. It does this by placing a pseudo-terminal between the  ap-
       plication and the real terminal.	It uses	the tecla command-line editing
       library to read input from the real terminal, then forwards  each  just
       completed  input	 line to the application via the pseudo-terminal.  All
       output from the application is forwarded	back  unchanged	 to  the  real

       Whenever	 the application stops generating output for more than a tenth
       of a second, the	enhance	program	treats the  latest  incomplete	output
       line  as	the prompt, and	redisplays any incompleted input line that the
       user has	typed after it.	Note that the small delay, which is  impercep-
       tible  to  the  user, isn't necessary for correct operation of the pro-
       gram. It	is just	an optimization, designed to stop the input line  from
       being redisplayed so often that it slows	down output.

       Note  that  the	user-level command-line	editing	facilities provided by
       the Tecla library are documented	in the tecla(7)	man page

       The one major problem that hasn't been solved yet, is how to deal  with
       applications  that  change  whether typed input is echo'd by their con-
       trolling	terminal. For example, programs	that ask for a password,  such
       as  ftp	and telnet, temporarily	tell their controlling terminal	not to
       echo what the user types. Since this request goes  to  the  application
       side  of	the psuedo terminal, the enhance program has no	way of knowing
       that this has happened, and continues to	echo typed input to  its  con-
       trolling	terminal, while	the user types their password.

       Furthermore, before executing the host application, the enhance program
       initially sets the pseudo terminal to noecho mode, so  that  everything
       that  it	sends to the program doesn't get redundantly echoed. If	a pro-
       gram that switches to noecho mode explicitly  restores  echoing	after-
       wards, rather than restoring the	terminal modes that were previously in
       force, then subsequently, every time that you enter a new input line, a
       duplicate copy will be displayed	on the next line.

       libtecla.a    -	 The tecla library.
       ~/.teclarc    -	 The tecla personal customization file.

       tecla(7), libtecla(3)

       Martin Shepherd	(



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