Slashdot is powered by your submissions, so send in your scoop

 



Forgot your password?
typodupeerror

Comment Re:Beards and suspenders. (Score 2) 637

Eww Octal??? My gosh, the PDP-11 is the purest of the pure! It is the excuse, the reason for Octal to exist!

No, octal was a much better fit for machines such as the PDP-6/PDP-10, PDP-5/PDP-8, and other multiple-of-6-bits-word-size machines. It worked well for PDP-11 instructions, not so well for PDP-11 data words if you cared about the individual bytes in the word.

Comment Re:Beards and suspenders. (Score 1) 637

None of these or any other internal arcana of c have anything to do with designing algorithms or programming computers.

Go tell that to the person who argued that programmer should become totally comfortable with bit-bashing, with pointers and pointer-array equivalency, and so on. "Pointer-array equivalency" (or "array-valued expression conversion to pointer-valued expression in most contexts") definitely counts as "internal arcana" of C and related languages.

Comment Re: Beards and suspenders. (Score 1) 637

whilst, in bar, foo is a pointer to int and [...]

Um, perfesser? It's a pointer to a char.

It's defined right there in the code as "char foo[1024];"

Yeah, I was thinking of another example I'd been working on when I wrote the answer; sorry about the minor brainfart.

In any case, yes, it is, indeed, a pointer to char in the code that I wrote, so just replace "int" with "char" in my answer and the answer still applies.

Comment Re: Beards and suspenders. (Score 1) 637

I know why they are different, but why don't you tell me why they are different and I'll see if you're right.

They're different because, in main, foo is an array of 1024 chars, and thus has a size of 1024 bytes, whilst, in bar, foo is a pointer to int and, unless you're running on a C implementation with 1024-byte pointers (I know of none, although I do know of implementations with 2-byte, 4-byte, 8-byte, and 16-byte pointers), its size won't be 1024 bytes.

Comment Re:Why isn't (Score 1) 116

Both UUCP and TCP/IP had email (although the ip side lagged badly, mail was really invented at Bell,

No, it wasn't.

IP made very crude versions of this ad took forever to do it)

Inter-host email came out the same year that UNIX first existed, and wasn't invented at Bell Labs. It ran over NCP, because TCP/IP didn't even exist yet.

SMTP, which ran over TCP and NCP, was first specified in 1982, slightly after TCP was first specified.

Comment Re:Beards and suspenders. (Score 4, Insightful) 637

You do know that sort of obsessive language-lawyering is exactly what turns people off to exploring C, right?

If it also turns them off from having to ask why this program

#include <stdio.h>

static void
bar(char *foo)
{
printf("sizeof foo is %u\n", (unsigned int)sizeof foo);
}

int
main(void)
{
char foo[1024];

printf("sizeof foo is %u\n", (unsigned int)sizeof foo);
bar(foo);
return 0;
}

doesn't print two identical lines - or from writing code that breaks because of this - that would be for the best.

Comment Re:Beards and suspenders. (Score 2) 637

Don't stop until you're totally comfortable ... with pointers and pointer-array equivalency ...

...which includes being aware that arrays in C are not just syntactic sugar around pointers.

This includes understanding what this means:

Except when it is the operand of the sizeof operator or the unary & operator, or is a string literal used to initialize an array, an expression that has type ‘‘array of type’’ is converted to an expression with type ‘‘pointer to type’’ that points to the initial element of the array object and is not an lvalue. If the array object has register storage class, the behavior is undefined.

(That's paragraph 3 of 6.3.2.1 "Lvalues, arrays, and function designators" in International Standard ISO/IEC 9899:1999, Second Edition, Programming languages — C.)

Comment Re:The WELL Was First - in 1985. Shein Is A Fraud. (Score 1) 116

Based on first-hand information, and belief, The Whole Earth 'Lectronic Link - The WELL, a product of Whole Earth Access - was first to offer dialup Internet accounts to paying customers.

Dialup accounts where you'd run SLIP over the dialup line, and IP packets you sent over the line got routed to arbitrary Internet hosts, and those hosts could route packets back to your machine which would receive them over the SLIP line?

If not, that's not a dialup Internet account. It might be a dialup shell account, or a dialup UUCP account, but it's not a dialup shell account. Barry's not saying he was the first to offer dialup shell accounts or dialup UUCP accounts, he's saying he was the first to offer dialup Internet accounts, letting your home machine directly connect to the Internet.

Comment Re:Freenets? (Score 1) 116

Yes, before my time, but Freenet has/had another meaning besides freenetproject.org

I.e., there were Freenets other than the one based on Ian Clarke's design?

(perhaps inspired their name though?)

Yes, I think the domain name "freenetproject.org" was chosen by the Freenet developers because they wanted a domain name containing "freenet".

(I.e., "freenetproject.org" appears to be the domain name for the Freenet Project; it's not just a bunch of people who liked Freenet and decided to have a domain name with "freenet" in it.)

Comment Re:Freenets? (Score 1) 116

As I stated, I used Archie, Gopher and IRC.. and as I just remembered EW-Too chat prgrams and MUDs/MUSHes/Etc... and was connecting to them directly from a shell account.... so by your definition that falls under ISP.

OK, I guess I didn't make it clear enough.

If you can send IP packets over your dialup connection and have them routed onto the Internet, and have IP packets from the Internet routed to your machine over the dialup connection, you're dialed into an ISP.

If you have to dial up a host and log in to getty over that dialup connection, then you're dialed up to a UNIX shell service provider, not an ISP, even if the UNIX host you've logged into happens to be connected to the Internet.

If a UUCP program on your machine has to dial up a host and log into a UUCP account over that dialup connection, then you're dialed up to a UUCP service provider, not an ISP, even if the host you're connecting to via UUCP can route emails to the Internet.

So unless you were using Archie and Gopher and IRC clients running on your machine at home, with those clients sending IP packets out over a SLIP connection and receiving IP packets from that SLIP connection, you were not dialing into an ISP.

Comment Re:Definitely not the first (Score 1) 116

"but they aren't sufficient to make you an ISP."

Of course they were. What does the I in ISP mean? "Internet".

If what you offer can interoperate with the network, you're an ISP.

If you can route packets from clients to the Internet, you're an ISP.

If you can only route mail messages and Usenet mail postings to the Internet, with your clients using UUCP to send them and receive them, and perhaps provide the ability to download and upload files using UUCP and maybe other uux-based services, you're a UUCP service provider, not an ISP.

Slashdot Top Deals

Work is the crab grass in the lawn of life. -- Schulz

Working...