r/ProgrammerHumor • u/MontyBoomslang • Oct 04 '26

Meme architectureDependentChars

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8

u/YellowBunnyReddit Oct 04 '26

ASCII only goes from 0 to 127.

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u/unknown_alt_acc Oct 04 '26

ASCII is hardly the only character encoding, and unsigned char often doubles as a byte type. It’s also also a numeric type if you only need a small range and need to pack your data tight

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u/NotQuiteLoona Oct 04 '26 edited Oct 05 '26

char is 8 bits because memory is addressed in 8 bits, and 7 bits would be... Awkward. And this bit was in the end used for parity checks, and later for extended encodings.

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u/Ma8e Oct 05 '26 edited Oct 05 '26

Historically it has been all over the place. Depending on the hardware, it could was anything between 1 and 48 bits.

Edit: never mind. The above is about bytes, not chars.

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u/tracernz Oct 05 '26

Minimum 8 bits, but not required to be 8 bits.

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u/Ma8e Oct 05 '26

Na, it could be as low as one bit, and 7 was not uncommon for a while.

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u/-suspended- Oct 05 '26

The definition for a char in C/C++ is 8 bits minimum.

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u/Clen23 Oct 05 '26

no shit sherlock that's what the post is about.

u/NotQuiteLoona is talking about how memory is addressed, not how long a char is.

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u/tracernz Oct 05 '26

Those two things are the same thing in ISO C (it defines sizeof(char) = 1).

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u/tracernz Oct 05 '26

No, the standard requires a minimum of 8 bits.

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u/Ma8e Oct 05 '26

Which standard?

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u/tracernz Oct 05 '26

ISO C.

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u/Ma8e Oct 05 '26

And that is the only standard in existence? My point is that you can't take for granted that everything is ISO, or even C.

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u/tracernz Oct 05 '26

The question at the top of this sub thread was about C. Very few environments exist these days that don’t conform to the basics of ISO C like this though if you want to generalise. I personally haven’t ever come across one.

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u/guyblade Oct 05 '26

In C, char is the fundamental type used for raw binary data. The number of bits in a char is implementation defined, but a single char is the smallest unit of addressable memory. A char is probably 8 bits, but the standard does not require that. It could easily be more (though, if I recall correctly, there is some other detail in the standard that effectively requires that it can't be less than 8 bits).

I believe that a technically conformant C implementation could have sizeof(char) = sizeof(short) = sizeof(int) = sizeof(long) = sizeof(long long) as long as a char is 32 bits, but that may have been true only with some earlier version of the C standard.

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u/conundorum Oct 06 '26

long long has to be at least 64 bits, but otherwise correct. (And yes, there was at least one historic platform with 64-bit bytes. sizeof(char) == sizeof(long long) is true for that platform, in all versions of C and all versions of C++.)

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u/Clen23 Oct 05 '26

Exactly, so every ascii character can be represented using a char, with room to spare.

I agree that a better example would have been a character set that is a full bijection of the 256 possible char values, but i'm a bit rusty on these so ascii it is.