C Strings and my slow descent to madness

Re:C Strings and my slow descent to madness by magicalhippo on Thursday April 06, 2023 @10:07AM (#35468482)

There is indeed just convention. The language defines string constants similar to what you say[1] (an array of characters, terminated by a null character), but in the language itself there's no way to declare that a function takes a string rather than a pointer to a character. Alternatively if you work with a fixed-sized character array, there's nothing separating it from "just" an array of characters that are not null terminated.

So that strcmp expects a string rather than a pointer to a character is just convention. In languages which actually has strings as a concrete concept, like say Pascal and derivatives, you can actually differentiate between those two cases.

[1]: https://www.gnu.org/software/gnu-c-manual/gnu-c-manual.html#...

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Re:C Strings and my slow descent to madness by int_19h on Thursday April 06, 2023 @03:47PM (#35473423)

That means that the strings aren't properly reflected in the type system. But the existence of string literals with a very definite in-memory layout means that it's not just a convention even so.

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Re:C Strings and my slow descent to madness by magicalhippo on Thursday April 06, 2023 @03:50PM (#35473467)

But you can't use those string literals in any way without relying on convention.

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Re:C Strings and my slow descent to madness by int_19h on Thursday April 06, 2023 @03:55PM (#35473520)

That was my point. Although you can, actually - since literals themselves are array-typed, you can sizeof them to get the character count without relying on null termination. It's even possible to get a non-null-terminated literal if the target array type is not large enough to fit null, e.g.:

   char s[3] = "foo"; // not null-terminated!

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Re:C Strings and my slow descent to madness by giantrobot on Thursday April 06, 2023 @05:36PM (#35474851)

> character count

Byte count.

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Re:C Strings and my slow descent to madness by int_19h on Thursday April 06, 2023 @06:26PM (#35475369)

If you want to be pedantic, "an object declared as type char is large enough to store any member of the basic execution character set". It doesn't actually have to be a byte.

In practice, in C context, character == char == byte. Other concepts have to use different names to avoid confusion with the language spec.

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Re:C Strings and my slow descent to madness by junon on Saturday April 08, 2023 @07:32AM (#35492325)

In C a 'char' is a 'byte', if we're going to be extra pedantic.

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