Michael Kallas writes:

I was looking for means to transfer files via nullmodem from my notebook to the desktop. I found the site archives.thebbs.org/ra90c.htm where many drivers (and different protocols) can be found.

Earlier I had already found Zest2.0 on simtelnet, but I did not get that one to cooperate with Linux lrzsz (first...).

I downloaded a whole bunch of programs and got then the clue to not run Linux rz/sz directly but as a driver in minicom (Telix-Clone). That way, I found two other programs (apart from the original dsz) that were capable to correctly start transfers in minicom: PDZM126 and TXZM241. The latter is shareware, but the first one seems to be a not-too-braindead public domain implementation. However, as in most cases, there are no sources included .

PDZM126 claims to run on every PC or Emulator using DOS3.0 or higher (FreeDOS works) and can be enhanced for Desqview or OS/2.

So, we definitely could need it for FreeDOS. But how could we convince the autor of making his program real Free Software?

There are said to be some PD+source versions of dsz, but
a) this one claims to be better
b) I haven't found them yet!

The only source I _know_ is existing and free is that of Linux lrzsz. But porting that to DOS would be a hazzle, wouldn't it?


Freya responds:

PDZ-Modem is wonderful!

I once wrote a comms program for dos which used external protocols for everything. I decided it wasn't worth trying to write internal protocols because it was much too hard and wouldn't be as good as the ones other people wrote.

I mostly used PDZ-Modem but I also used a program called IceZ-Modem too, which was supposed to be faster and was supported on the BBS systems I used.

Actually my comms program was originally supposed to be entirely made up from modular bits and pieces but it didn't really end up that way.

Anyway, I spent ages writing this program till it worked better than any other program I had on the various BBS systems I used. The only problem I had was that there was two standards for how the cursor keys operated and I never worked out how to switch between the two automatically, only manually. Most comms software couldn't do this anyway.

Before you ask, I had a harddisk failure and lost the source code to this program, I still have the latest binaries and use it a fair bit just to transfer the odd thing from over a serial connection (with PDZmodem, which really is wonderful), actually that's not entirely true, I have some much older source to the program but frustratingly old compared to the binary which fixed lots of things. It's probably not worth having though because now there are not many BBS systems out there I would guess, and for just doing simpler things I bet that new little terminal program mentioned in the Freedos news is much better, it sounds really good and probably more tiny than mine! Most of the special things my comms program did were to cope with all those silly BBS systems with really complicated Ansi menus with cursor controllable menu bars and doors and all that stuff! I stopped working on it after this because I was depressed at having only the older source and because the internet came along!

If anyone wants to look at/ play with it, it might be easy for me to dig out a copy of the binary at the moment, as my laptop is currently in floppy drive mode and the comms program is on the main hardisk. (I have another harddisk which is mutually exclusive with the floppy drive which makes for an interesting time!) Give me a shout if you want to take a peek but don't leave it too long because I'll probably mess with my laptop again! :)

Yes it is a terrible shame there is no source to PD-Zmodem. I used to download various Z-Modem source code, and it mostly seemed unfathamable, and when it compiled it never seemed to work properly.

Anyway, PD-Zmodem was the best Zmodem implementation I ever saw with a Free liscence. Its really stable and fast and nice looking.

I wouldn't bother looking for a better version, unless someone ports that linux program to dos. :)