Forum Rules and Etiquette

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This forum is part of our mission to promote the preservation of vintage computers through education and outreach. (In real life we also run events and have a museum.) We encourage you to join us, participate, share your knowledge, and enjoy.

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Rule 1: Remain civil and respectful

There are several hundred people who actively participate here. People come from all different backgrounds and will have different ways of seeing things. You will not agree with everything you read here. Back-and-forth discussions are fine but do not cross the line into rude or disrespectful behavior.

Conduct yourself as you would at any other place where people come together in person to discuss their hobby. If you wouldn't say something to somebody in person, then you probably should not be writing it here.

This should be obvious but, just in case: profanity, threats, slurs against any group (sexual, racial, gender, etc.) will not be tolerated.

Rule 2: Stay close to the original topic being discussed
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Rule 3: Contribute something meaningful

To put things in engineering terms, we value a high signal to noise ratio. Coming here should not be a waste of time.
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Rule 4: "PM Sent!" messages (or, how to use the Private Message system)

This forum has a private message feature that we want people to use for messages that are not of general interest to other members.

In short, if you are going to reply to a thread and that reply is targeted to a specific individual and not of interest to anybody else (either now or in the future) then send a private message instead.

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Why do we have this policy? Sending a "PM Sent!" type message basically wastes everybody else's time by making them having to scroll past a post in a thread that looks to be updated, when the update is not meaningful. And the person you are sending the PM to will be notified by the forum software that they have a message waiting for them. Look up at the top near the right edge where it says 'Notifications' ... if you have a PM waiting, it will tell you there.

Rule 5: Copyright and other legal issues

We are here to discuss vintage computing, so discussing software, books, and other intellectual property that is on-topic is fine. We don't want people using these forums to discuss or enable copyright violations or other things that are against the law; whether you agree with the law or not is irrelevant. Do not use our resources for something that is legally or morally questionable.

Our discussions here generally fall under "fair use." Telling people how to pirate a software title is an example of something that is not allowable here.

Reporting problematic posts

If you see spam, a wildly off-topic post, or something abusive or illegal please report the thread by clicking on the "Report Post" icon. (It looks like an exclamation point in a triangle and it is available under every post.) This send a notification to all of the moderators, so somebody will see it and deal with it.

If you are unsure you may consider sending a private message to a moderator instead.

New user moderation

New users are directly moderated so that we can weed spammers out early. This means that for your first 10 posts you will have some delay before they are seen. We understand this can be disruptive to the flow of conversation and we try to keep up with our new user moderation duties to avoid undue inconvenience. Please do not make duplicate posts, extra posts to bump your post count, or ask the moderators to expedite this process; 10 moderated posts will go by quickly.

New users also have a smaller personal message inbox limit and are rate limited when sending PMs to other users.

Other suggestions
  • Use Google, books, or other definitive sources. There is a lot of information out there.
  • Don't make people guess at what you are trying to say; we are not mind readers. Be clear and concise.
  • Spelling and grammar are not rated, but they do make a post easier to read.
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Decided to start learnig C

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    Nope--I'd love to go into details, but this is a C thread and I don't want to derail it.
    Reach me: vcfblackhole _at_ protonmail dot com.


      Mind you, its writing logical statements in SQL that i don't like, only had to have three IIF statements in one I did yesterday and it still looks like an unreadable mess.
      Current fleet
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        Originally posted by goostaw View Post
        Recently I discovered how c / c ++ compiler „sees” array syntax.
        #include <stdio.h>
        int main()
        	char a[] = { "run" };
        	*a = 2[a];     // :)
        	printf( "%s", a );
        	return 0;
        Interestingly, none of my professional ( c#, c++, python, java ) programmer friends knew why it works
        That's because they never coded in assembler.
        "nun" that's a neat trick.



          Originally posted by jlang View Post
          That's because they never coded in assembler.
          "nun" that's a neat trick.
          I get it now - the first byte of a is getting set to essentially a=2, replacing the r with an n.


            Originally posted by ClassicHasClass View Post
            In the C standard, a[i] is equivalent to *(a+i). Since addition is commutative, i[a], as it is *(i+a), is equivalent.

            This is a nice deeper dive:
            To be pedantic, it's *(a + i * sizeof(array_element_type)).


              Originally posted by ClassicHasClass View Post
              Or, you could post your example rather than referring to a book I have to go track down, ahem.
              Or you could have clicked on the link and watched the magic of the internet unfold before your very eyes.


                To be pedantic, it's *(a + i * sizeof(array_element_type)).
                Point taken.

                Or you could have clicked on the link and watched the magic of the internet unfold before your very eyes.
                Point not taken. There is no link to that book in his post:
                I use my C128 because I am an ornery, stubborn, retro grouch. -- Bob Masse
                Various projects and oddities:
                Machine room:



                  Abstract here:


                    I strongly recommend The C Puzzle Book

                    Also, one sign that code was written by a thoughtful programmer is the extensive use of typedef and enum statements.

                    If you're writing code that assumes a certain integer length, be sure to #include <stdint.h> and use the typedefs defined there.
                    Last edited by Chuck(G); November 16, 2020, 03:40 PM.
                    Reach me: vcfblackhole _at_ protonmail dot com.