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Comment by jmnicolas | Hacker News Reader

I have no knowledge of C, but reading their code I was surprised to see some gotos ... is this OK in C to use goto ?

It's a very common C error-handling pattern, essentially emulating RAII with forwards-only function-local goto statements. It's possible to do without, but that tends to yield much more deeply nested code (especially if it's complex) and possibly some amount of duplication.

See http://eli.thegreenplace.net/2009/04/27/using-goto-for-error... for a short rundown, or http://blog.regehr.org/archives/894 where regehr — who works specifically in correctness and verifiability — states:

> many people, including me, prefer the goto version

Most languages use unconditional jumps to break flow when necessary, it might be called "exception" instead of "goto" but it's conceptually the same thing.

In many high level languages a break, continue, pass, that sort of thing (where you want to skip or escape a loop iteration) is usually implemented with a goto as well.

Also, a common use of goto in C is when you're doing something in nested for loops and want to break out of all of them. A goto is actually much cleaner here than using sentinel values or boolean flags, or naughty things like setting your loop variables to be outside of the conditional bounds.

Well if you go that way, fundamentally all structured programming techniques are implemented with a goto, that's what jumps are.

C lacks exception handling. goto is used to implement it.

Every conditional is a goto (jump) at the machine level.

Yes.

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