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Ask Slashdot: What Are Some Things That Every Hacker Once Knew? (ibiblio.org)
Open source guru Eric Raymond turns 60 this year, prompting this question from an anonymous reader:
Eric Raymond's newest writing project is "Things Every Hacker Once Knew," inspired by the day he learned that not every programmer today's knows the bit structure of ASCII. "I didn't write it as a nostalgia trip -- I don't miss underpowered computers, primitive tools, and tiny low-resolution displays... In any kind of craft or profession, I think knowing the way things used to be done, and the issues those who came before you struggled with, is quite properly a source of pride and wisdom. It gives you a useful kind of perspective on today's challenges."
He writes later that it's to "assist retrospective understanding by younger hackers so they can make sense of the fossils and survivals still embedded in current technology." It's focusing on ASCII and "related technologies" like hardware terminals, modems and RS-232. ("This is lore that was at one time near-universal and is no longer.") Sections include "UUCP and BBSes, the forgotten pre-Internets" and "The strange afterlife of the Hayes smartmodem" (which points out some AT commands survived to this day in smartphones). He requests any would-be contributors to remember that "I'm trying to describe common knowledge at the time." This got my thinking -- what are some that every programmer once knew that have since been forgotten by newer generations of programmers?
Eric Raymond is still hard at work today on the NTPsec project -- a secure, hardened, and improved implementation of Network Time Protocol -- and he promises donations to his Patreon page will help fund it. But what things do you remember that were commonplace knowledge "back in the day" that have now become largely forgotten? Leave your best answers in the comments. What are some things that every hacker once knew?
He writes later that it's to "assist retrospective understanding by younger hackers so they can make sense of the fossils and survivals still embedded in current technology." It's focusing on ASCII and "related technologies" like hardware terminals, modems and RS-232. ("This is lore that was at one time near-universal and is no longer.") Sections include "UUCP and BBSes, the forgotten pre-Internets" and "The strange afterlife of the Hayes smartmodem" (which points out some AT commands survived to this day in smartphones). He requests any would-be contributors to remember that "I'm trying to describe common knowledge at the time." This got my thinking -- what are some that every programmer once knew that have since been forgotten by newer generations of programmers?
Eric Raymond is still hard at work today on the NTPsec project -- a secure, hardened, and improved implementation of Network Time Protocol -- and he promises donations to his Patreon page will help fund it. But what things do you remember that were commonplace knowledge "back in the day" that have now become largely forgotten? Leave your best answers in the comments. What are some things that every hacker once knew?
Use the -d flag with pkunzip, otherwise, you might end up with a big stinking mess.
What Are Some Things That Every Hacker Once Knew?
Do you mean hacker as in programmer or hacker as the media usis it to describe a digital burlgar? If you mean the former, these days it seems to be simple stuff like checking for open ports with telnet and then having fun by typing in protocol messages: http://www.shellhacks.com/en/S..., or even simpler stuff like editing documents with vi and using command line programming tools. These used to be things that every programmer knew, I learned this in school but many of our new recruits seem to be totally unaware of this stuff. I've written programs tens of thousands of lines long with nothing but vi, gcc/g++, make, tcpdump+Wireshark, valgrind, vi and a few other choice commandline monsters but these days the GUI generation seems to need a GUI editor, preferably a GUI IDE, a GUI networking tool, a GUI debugger, etc... to do simple stuff. I don't usually even need a debugger, I can normally figure out what is wrong without one. A few years ago I was handed a .NET assignment. After much complainign and whining (Unix guy through and through) I coded it up using that primitive little Windows CMD terminal, a freely available .NET compiler and vi/make before the IT department got around to installing Visual Studio. The really funny thing was that even some seasoned .NET developers were surprised to see you could (a) run vi/make and other GNU tools on Windows and (b) compile .NET code from the command line: https://msdn.microsoft.com/en-.... BTW, and this is probably heresy around here, but I really like how Microsoft seems to have a well documented API for everything as long as you are willing to bother learning .NET or Visual Basic.
The "control characters" have their own special position in ASCII, as the codes below the space character: 0x00 through 0x1F.
Yet, for some reason, there is one more sort-of control character outside that range: DEL, which is 0x7F. This bit of lore is actually from before my time, but I know why.
People used to actually use paper-punch machines to punch input tapes. What could you do if you mis-punched? There's no good way to fill in holes you didn't mean to punch, but you could go back and punch more holes. ASCII is a 7-bit standard and DEL is all 7 bits set. So, if you hit the wrong key on the punch, you could hit DEL and it would punch out all the rest of the holes, making 0x7F or DEL, and the paper tape reader would simply ignore any DEL characters it saw.
Oh, I guess anyone who can use Wikipedia didn't need me to find this out.
P.S. I didn't actually know why the carat notation for DEL is ^?, but Wikipedia explains that as well. Neat!
lf(1): it's like ls(1) but sorts filenames by extension, tersely
The zero page on e.g., a 6502 consisted of the first 256 bytes in memory, so the address of any byte therein was only a single byte in stead of two. Access therefore was faster on that page than of all other parts of memory.
The Apple II was my first computer. I bought it when I was thirty, in 1979. I then was an art historian, looking for new ways to administrate art collections. It really changed my life
Paai
Do you mean hacker as in programmer or hacker as the media usis it to describe a digital burlgar?
It's an ESR article. Eric never uses the word "hacker" in the latter sense.
Disinfect the GNU General Public Virus!
Ahh yes the good old days of XOR-based linked lists.
Someone had to do it.
In .NET, no. About 6 years ago I was tasked with rewriting our base-64 encoder/decoder. We were using MS's built-in encoder and is was too slow to handle a multi-GB inbox (we sold a shrink-wrap email server for ISP's). First I rewrote it in regular math operations, and it was faster, but not fast enough. I rewrote it again using bit-shifting operations and it was an order of magnitude faster. I really had to reach back into my days coding MUD's in C for that. We really take our faster computers for granted, and our code is far from the level of optimization we were once required to achieve.
FIDO.
Email delivery in single-digit days was shockingly cool.
ASCII pr0n.
Dial strings to coax another .5k baud out of that Hayes clone.
deleting the extra space after periods so i can stay relevant, yeah.