ZMODEM • Hacker News Board

Re: ZMODEM

#101

Post by koytch » Sun, Oct 23, 2016, 10:48 PM UTC

Zmodem's code is uglier than Kermit's IMO. Gods help you if you have to read either, but Kermit is written better and EK is almost understandable once you fold all unneeded #define's.

I'm surprised no-one mentioned the venerable UUCP. It has more variants than X/Y/Zmodem combined: at least 12.

Re: ZMODEM

#102

Post by desireco42 » Mon, Oct 24, 2016, 12:29 AM UTC

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!

I think autostart was huge for me, aside from faster transfers. It was ages ago, yet it was like yesterday.

Re: ZMODEM

#103

Post by jamesbrownuhh » Tue, Oct 25, 2016, 3:57 PM UTC

I remember trying out Zmodem early on, only to find that it obviously had some kind of bug in that it would reliably and consistently drop the line after a certain amount of data had been transferred.

Not so, of course - but unlike Xmodem and Ymodem which acknowledged every packet (and slowed things down), Zmodem would not constantly ack back to the host unless there was an error... So this triggered the modem's inactivity timeout, since despite the constant stream of data coming down from the remote system, there were no "keystrokes" or other packets travelling in the other direction. Hence, after X minutes... Line drop.

Easily sorted with a few AT commands, eventually. :)