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Comment by tptacek | Hacker News Reader

In C, what stat does is how you return multiple values from a function.

lstat has the same signature as stat: it passes the stat structure back through an output pointer.

But not if you're a literal lunatic who thinks that because you literally used the word return with an error code that's what it returns. And. Only. That.

To be fair, the rest of the questions were demonstrably pedantic, and I would completely expect a question like this to be on the bill of fare:

   Q: What does lstat return?
   A: A struct
   >> Wrong, it returns an error code

That type of technical specificity about what well-known functions return is absolutely something I've heard people use as an interview question. Knowing it returns an error code (rather than the value you want) seems like a good indicator of "has actually coded in C" (whereas many other languages return the value you want and raise an exception if it had an error).

>In C, what stat does is how you return multiple values from a function.

IIRC, you can return structs from functions in C. You have to access the values in the returned struct with dot notation, of course, like point.x .

Pre-ANSI C may not have had this, but later, it did. Remember reading it in the 2nd (ANSI) edition of the Kernighan & Ritchie C book, and also used it myself in some programs.

https://www.google.co.in/?q=can+you+return+a+structure+in+c

Edit:

Might want to consider the cost of copying, depending on the perf requirements, size of the struct, whether the function call is in a tight loop, etc.

returning multiple values was the key part of the sentence

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