Ruby for IBM terminal emulation

ruby-talk
1

hi,

I am not sure if this is the right address to send my question …so… !

Is Ruby language a good choice for a terminal emulation software with
an IBM mainframe ?
i have to convert and port a terminal emulator currently in “C” lang
for communicating with the IBM mainframe.
It is in the MSWindows OS platform and i want to port it to the
Gnu/Linux OS platform but will it work if the client has another OS/s?
Would Ruby be a better option to C++ ?
thanks for your time,

···

=====
{vidya}

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2

I’d guess that your “C” program is making use of the getch() function
(directy or indirectly).
Because this isn’t available with all compilers, Ruby uses getchar()
which, under Win32, gets too much “help” from DOS (e.g. DOS echoes
the characters as you type but doesn’t return the input until getchar()
sees end-of-line). I don’t know *nix but I’m fairly sure this problem
isn’t there.

So, a compiled-for-Win32 Ruby interpreter has this anomaly built-in.

You can work-around by checking the Ruby platform in a script and calling
Win32API but then you haven’t got one script that will work for all.

I would look at how easy it might be to convert the Win32 bits to
more portable “C” and try ramming the prog. through a GNU compiler ?

Use Ruby for your next project :slight_smile:

daz

···

“{ vidya }” vidu108@yahoo.com wrote:

hi,

I am not sure if this is the right address to send my question …so… !

Is Ruby language a good choice for a terminal emulation software with
an IBM mainframe ?
i have to convert and port a terminal emulator currently in “C” lang
for communicating with the IBM mainframe.
It is in the MSWindows OS platform and i want to port it to the
Gnu/Linux OS platform but will it work if the client has another OS/s?
Would Ruby be a better option to C++ ?
thanks for your time,

3

daz wrote:

hi,

I am not sure if this is the right address to send my question …so… !

Is Ruby language a good choice for a terminal emulation software with
an IBM mainframe ?
i have to convert and port a terminal emulator currently in “C” lang
for communicating with the IBM mainframe.
It is in the MSWindows OS platform and i want to port it to the
Gnu/Linux OS platform but will it work if the client has another OS/s?
Would Ruby be a better option to C++ ?
thanks for your time,

I’d guess that your “C” program is making use of the getch() function
(directy or indirectly).
Because this isn’t available with all compilers, Ruby uses getchar()
which, under Win32, gets too much “help” from DOS (e.g. DOS echoes
the characters as you type but doesn’t return the input until getchar()
sees end-of-line). I don’t know *nix but I’m fairly sure this problem
isn’t there.

So, a compiled-for-Win32 Ruby interpreter has this anomaly built-in.

Hmm, I think if you “grab” a character you don’t get an echo.

You can work-around by checking the Ruby platform in a script and calling
Win32API but then you haven’t got one script that will work for all.

This might be acceptable for him. Is Win32API a part of the
standard Ruby distribution on Windows? If so, the difference
should be imperceptible to the user.

Hal

···

“{ vidya }” vidu108@yahoo.com wrote:

4

daz wrote:

hi,

I am not sure if this is the right address to send my question …so… !

Is Ruby language a good choice for a terminal emulation software with
an IBM mainframe ?
i have to convert and port a terminal emulator currently in “C” lang
for communicating with the IBM mainframe.
It is in the MSWindows OS platform and i want to port it to the
Gnu/Linux OS platform but will it work if the client has another OS/s?
Would Ruby be a better option to C++ ?
thanks for your time,

I’d guess that your “C” program is making use of the getch() function
(directy or indirectly).
Because this isn’t available with all compilers, Ruby uses getchar()
which, under Win32, gets too much “help” from DOS (e.g. DOS echoes
the characters as you type but doesn’t return the input until getchar()
sees end-of-line). I don’t know *nix but I’m fairly sure this problem
isn’t there.

So, a compiled-for-Win32 Ruby interpreter has this anomaly built-in.

Hmm, I think if you “grab” a character you don’t get an echo.

His emulator in “C” will be doing that but if I run this Ruby:

$stdout.sync=true
c = STDIN.getc
p ‘END’

and type z

I see z alone on the console.

When I press return, I see z on line 1 and “END” on line 2.
I think you’ll agree, I “grabbed” the z, didn’t want to see it
but did, didn’t want to press return but had to or else I never
would have seen ‘END’.

You can work-around by checking the Ruby platform in a script and calling
Win32API but then you haven’t got one script that will work for all.

This might be acceptable for him. Is Win32API a part of the
standard Ruby distribution on Windows?

Yes.

If so, the difference should be imperceptible to the user.

This is based on one of the Win32API examples:

require ‘Win32API’
getch = Win32API.new(“crtdll”, “_getch”, , ‘L’)

c = getch.Call
p ‘END’
p c.chr

Displays “END” as soon as I press z (which isn’t echoed),
then prints the result I requested (“z”) and terminates.

So it’s possible.

Hal

daz

(Apologies to treasurers and students of the English language
for the hyphen in “… has this anomaly built-in”.)

···

“Hal Fulton” hal9000@hypermetrics.com wrote:

“{ vidya }” vidu108@yahoo.com wrote:

5

This is based on one of the Win32API examples:

require ‘Win32API’
getch = Win32API.new(“crtdll”, “_getch”, , ‘L’)

c = getch.Call
p ‘END’
p c.chr

Displays “END” as soon as I press z (which isn’t echoed),
then prints the result I requested (“z”) and terminates.

So it’s possible.

That is what I mean when I say “grabbing” a character. That’s
not standard usage, it’s just my personal slang.

Hal