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ZMODEM

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Re: ZMODEM

#31

Post by tyingq »

lokedhs wrote: post #27
tyingq wrote: post #9

Kermit was in the same space as Zmodem. I remember it fondly, as they were very progressive around "open source" way back in the early 90's, and probably earlier. They accepted what was essentially a "pull request" over USENET discussions forums from me to add a feature. http://www.kermitproject.org/ckfaq.html

Except they were never open. You could download the code, but you were not allowed to distribute modifications to it. The project was cancelled in 2011, and according to the web page it's open source now, and I think that the open sourcing didn't happen until then.

I did put "open source" in quotes for that reason. At the time, it what somewhat novel to be able to get the source code at all, and even more novel that the writers would accept code from end users to put back into the product.

Re: ZMODEM

#33

Post by qwertyuiop924 »

tyingq wrote: post #31
lokedhs wrote: post #27

Earlier quoted context omitted.

Except they were never open. You could download the code, but you were not allowed to distribute modifications to it. The project was cancelled in 2011, and according to the web page it's open source now, and I think that the open sourcing didn't happen until then.

I did put "open source" in quotes for that reason. At the time, it what somewhat novel to be able to get the source code at all, and even more novel that the writers would accept code from end users to put back into the product.

>At the time, it what somewhat novel to be able to get the source code at all

Really? IIRC, in Jason Scott's excellent BBS documentary (you should go watch it. Like, right now. It's that good), Thom Henderson (from SEA. Remember them? I don't, because I wasn't alive. Which is why I have to rely on documentaries) said that it was expected in UNIX circles, which is where Kermit originated.

Or were you on PC? I don't know, I wasn't alive.

Re: ZMODEM

#34

Post by qwertyuiop924 »

chrisfinne wrote: post #12

This submission is a ploy by the NSA and advertisers to further refine their demographic slot of "old hackers". Kermit, zmodem, bbs, baud. South Park's Member Berries are in full force here. CoCo forever!

Hey, I recognized all of that software save ZMODEM, and I'm not out of highschool yet! Then again, I only know about it because I read The Cuckoo's Egg, and am totally obsessed with computer history.

But I think most of us would recognize baud, even if we've never worked with anything that you would measure in it.

Re: ZMODEM

#35

Post by pimeys »

ghaff wrote: post #14
anexprogrammer wrote: post #3

> Introduced 1986; 30 years ago Now I feel old. I remember when this was new and clever. Made downloading from BBS's much nicer over XModem. At 2400 baud or whatever was current then!

There were a bunch of different something-Modems around that time that fiddled around with window sizes, retransmission approaches, batch transmission, and so forth. In case anyone is wondering, there was a YModem (also developed by Forsberg) in addition to XModem and ZModem along with various variants. I even interned for a small company one summer that implemented one of these for a timesharing service using Prime…

SModem was the best. You could chat with people while downloading files.

Re: ZMODEM

#36

Post by ptaipale »

anexprogrammer wrote: post #3

> Introduced 1986; 30 years ago Now I feel old. I remember when this was new and clever. Made downloading from BBS's much nicer over XModem. At 2400 baud or whatever was current then!

Yup, the first problem with Xmodem was that it transferred sectors (as in CP/M) and thus file size was always padded with zeros to a multiple fof 128 bytes.

Then came Ymodem which fixed this, and then Zmodem which was considerably faster (windowing protocol) and allowed resuming interrupted transfers and handled CRC checksums.

Re: ZMODEM

#37

Post by qwertyuiop924 »

BBSes: Yet another technology I missed, because I wasn't alive. Ah well.

Speaking of things that I wasn't there for, did you know TinyTIM's still up? Sketch (perhaps better known around here as Jason Scott) hasn't actually killed it because it's so cheap to run. Mind, nobody's actually around anymore, but you can explore the relics of a once-great civilization over at http://www.tim.org/.

Re: ZMODEM

#38

Post by tyingq »

qwertyuiop924 wrote: post #33
tyingq wrote: post #31

Earlier quoted context omitted.

I did put "open source" in quotes for that reason. At the time, it what somewhat novel to be able to get the source code at all, and even more novel that the writers would accept code from end users to put back into the product.

>At the time, it what somewhat novel to be able to get the source code at all Really? IIRC, in Jason Scott's excellent BBS documentary (you should go watch it. Like, right now. It's that good), Thom Henderson (from SEA. Remember them? I don't, because I wasn't alive. Which is why I have to rely on documentaries) said that it was expected in UNIX circles, which is where Kermit originated. Or were you on PC? I don't kn…

For commercial end users of SunOS, Ultrix, etc, most of what we used was closed source.

Kermit was not the only software you could get source code for. However, the entire ecosystem was much smaller than what exists today.

I'll concede it may have been different in more academic environments.

Re: ZMODEM

#39

Post by kevin_thibedeau »

The sad thing is I'm stuck on a codebase that uses Xmodem for core operations and have to forgo such niceties as having file name, size, and timestamp automatically handled. I don't know why they didn't just implement Ymodem like they should have.

Re: ZMODEM

#40

Post by qwertyuiop924 »

tyingq wrote: post #38
qwertyuiop924 wrote: post #33

Earlier quoted context omitted.

>At the time, it what somewhat novel to be able to get the source code at all Really? IIRC, in Jason Scott's excellent BBS documentary (you should go watch it. Like, right now. It's that good), Thom Henderson (from SEA. Remember them? I don't, because I wasn't alive. Which is why I have to rely on documentaries) said that it was expected in UNIX circles, which is where Kermit originated. Or were you on PC? I don't kn…

For commercial end users of SunOS, Ultrix, etc, most of what we used was closed source. Kermit was not the only software you could get source code for. However, the entire ecosystem was much smaller than what exists today. I'll concede it may have been different in more academic environments.

shrugs

Of course, in the early days of unix, you got the OS in source form, but those were long gone by then. AFAIK, a lot of independently developed utilities were distributed in source form, in part because it was common to have to edit the sources and compile yourself if you weren't on the exact same architecture as the author. But that's just what I've heard.

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