Telnet.ocx?

[yellowbutterfly]

hey, a noob VB6 programmer here...

anyone know where can i get an activex telnet for free?

thanks.

[dilettante]

Can you offer more details about what you need?

Telnet server or client?

If a client, blocking calls or fully async? True Telnet or just raw TCP?

Terminal type support required? Which type(s)?

Are you really after a "terminal" UI control (i.e. a terminal display character grid control that handles ANSI escape sequences)?

[Hack]

You can create your own TelNet client using VB's Winsock control.

[vbleet]

True Telnet will allow only 1 connection per IP well that is from my knowledge with some servers i have messed around with ;)

[yellowbutterfly]

You can create your own TelNet client using VB's Winsock control.

how? more details please.

i'm trying to make a program that connects to a unix telnet server. i'm currently using reflection basic script. i'm really interested in using vb, i think i can make better and more appealing programs w/ what vb has to offer.

thanks for the replies :wave:

ho

[Hack]

See if this (http://www.a1vbcode.com/app-311.asp) example helps.

[yellowbutterfly]

Can you offer more details about what you need?

Telnet server or client?

If a client, blocking calls or fully async? True Telnet or just raw TCP?

Terminal type support required? Which type(s)?

Are you really after a "terminal" UI control (i.e. a terminal display character grid control that handles ANSI escape sequences)?

wow...i'm not really familiar about "async" or "ANSI" stuff :eek:
anyway, i just wanted a terminal emulator (like VT100) that i can use to extract server response and contrl the program. and i think vb refers to that as an object? (please enlighten me on this one if i'm off-track)

thanks :wave:

[dilettante]

ANSI and VT100 are very similar.

With Telnet you normally have three layers of things going on:

TCP protocol over IP.
Telnet protocol over TCP.
Terminal emulation (such as VT100) over Telnet.

Depending on the component you use, your program may have to provide one or more "layers" of the stacked protocols.

The most primitive would be to use the Winsock control. Working from there your program would be responsible for handling both the Telnet protocol and the terminal emulation.

In many cases a Telnet server may be "dumb" and only support a simply TTY terminal type. This is like a very simple subset of VT100, and does not add VT100 escape sequences interspersed throughout the data. Some servers are smarter than this, and will accept terminal type option negotiation for several terminal types. For a program like yours you would probably want to negotiate a terminal type such as TTY or NVT. These will add the least "garbage" to the raw data.

Some "Telnet" servers aren't Telnet at all. They are really dumb. They actually just support a TCP stream with CR, LF, or CRLF as line delimiters. These are ideal for use with the Winsock control.

Most Telnet servers really are Telnet servers though. This means either more work in your program or else a client component that is smarter than the Winsock control alone.


There are a few "smarter" Telnet client components out there for free. Most of these only support synchronous operation though, since they were really designed to be used in ASP pages where the script doesn't support an event processing model, unlike a VB program.

They can still be pressed into service in VB though. Just be aware that in a VB forms program you may have your forms appear to "lock up" while the logic is blocked awaiting data from the server. They don't support any kind of "data arrival event" so your program has to hang on any sort of read method you call with these synchronous objects.

There are also smarter components that can support VB-style async programming. I just don't know of any free ones.


So, you're down to a few choices:

Hope for a really dumb server.
Live with a smart but sync-only free component.
Pay for a smart but async-capable component.
Roll your own logic to wrap the Winsock control.

Ideally somebody would have done the last one a long time ago... and made the source code freely available. Alas, lots of people have Telnet client code written in VB, and some even share it - but most don't understand the concept of code re-use in VB. They write the code as a "big ball of mud" instead of encapsulating it as a UserControl source module or a compiled OCX.

But just maybe somebody here has done just that, and might offer an existing VB Telnet client UserControl.

[compad]

Hello Friends,

How can i set vt100 with my mscomm component of Visual Basic 6.

plz guide me.

Thanks in advance,

Adarsh Patel