[Info-vax] VMS Features I Wish Linux Had

[John E. Malmberg]

On 6/9/2016 10:37 PM, lawrencedo99 at gmail.com wrote:
>
> The other one is the terminal driver. My first impression of Unix
> was  what a crap terminal driver it had, that echoes everything as
 > soon as it’s typed. Seems like no other system has seen fit to
 > emulate the thoughtful VMS feature of not echoing anything until
 > it is actually being recognized as input to a program.

Which can let text not intended to be echoed like passwords leak to the 
terminal output.

 > And of course note the versatility of IO$_READPROMPT--you could do
 > all your terminal I/O with just this one call!

The terminal driver design and much of the VMS I/O design makes it easy 
to offload I/O processing to additional systems.

Which means that the IO$_READPROMPT processing could in theory be 
entirely handled by a terminal server or local CPU on the serial interface.

This is something that could be used with future paravirtualized drivers 
for emulators and VMs to improve performance.

> Many interactive utilities on Linux use a library called GNU
> Readline.   This gives you an interactive prompt with command-line
 > editing, persistent searchable history and so on. But it cannot
 > automatically refresh the current line if anything (like output
 > from another process) should overwrite it--you have to manually
 > trigger that yourself.

One issue with the VMS terminal line editing is because it is handled in 
the driver, it does not have access to the filesystem to allow it to do 
filename completion.

A port of GNU readline is imbedded in the GNV Bash kits.  I am hoping 
eventually it will be available as a standalone package.  I am focusing 
on getting the other GNV components built as standalone packages first.

Regards,
-John
wb8tyw at qsl.net_work