How can C Programs be so Reliable?
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How can C Programs be so Reliable?
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Re: How can C Programs be so Reliable?
#2The author has a unique perspective since he - somehow - skipped learning C until now. He programmed assembly before, and from his other work he clearly is familiar with dynamic and more modern languages.
Consequently, his perspective on C is that of somehow who is new to the language, yet also understands both the fundamentals of what his code will compile down to, and the higher level facilities that later languages and programming models abstracted away.
Re: How can C Programs be so Reliable?
#3The thing about C is that you are generally very aware of the side effects. Aside from the libraries you use, the (data) structures are yours. When you set something to NULL, you know damn well that that means to you.
As the author alludes to as well - in C you're made more aware of the error conditions you can handle and the ones you can't. So you can code to a level of robustness... Exceptions in Java are all well and good, but I haven't seen many implementations that do anything with IOException except for cascade it.
This works really well for programs/modules that can fit in the head of a single programmer. When you go beyond that it gets pretty messy - which is where some of the advantages of metaphors like OO start to help... Course, there is the argument that modules should never get that big, but that's another debate.
Re: How can C Programs be so Reliable?
#4If, as in the case of extsmail, one wants to be robust against errors, one has to handle all possible error paths oneself.
That's not really a bad thing, as the author points out.
One thing I've always felt a sense of dread about in C# and Java (last Java I did was back in 2001) is that I never truly knew what errors were lurking with their exception handling. It would be really nice if all error possibilities were listed in the documentation so I could pick precisely what to handle.
Re: How can C Programs be so Reliable?
#5People often write in higher level languages because they want lots of bad code fast. Almost all business applications are CRUD apps (create/retrieve/update/destroy) with some business logic, and they're generally written in C#. The app may crash when you click the wrong button, but the app is cheap to develop and the programmers are easily replaceable.
Of course I'm generalizing, and a lot of C# programmers write great and reliable code. The point is that they often don't -need- to write great code, because lousy code is good enough for all business purposes (except when the software is your product, which is rarely the case).
The second issue is that people who choose C for their projects tend to (a) understand low-level concepts, (b) care about speed / memory usage / reliability / dependencies, (c) don't consider development time that important. That you create more reliable software that way is obvious - the same programmers would create reliable software in C# (or similar language). But there aren't many situations in which development speed doesn't matter, speed and memory usage don't matter, dependencies don't matter but, for some reason, reliability is very important.
Re: How can C Programs be so Reliable?
#6If, as in the case of extsmail, one wants to be robust against errors, one has to handle all possible error paths oneself. That's not really a bad thing, as the author points out. One thing I've always felt a sense of dread about in C# and Java (last Java I did was back in 2001) is that I never truly knew what errors were lurking with their exception handling. It would be really nice if all error possibilities were l…
It's even worse. For top level functions it can throw the UNION of the exceptions thrown by the functions it calls. Therefore, by changing a low level function's exception signature the exception signature of all higher level functions changes too. That always worried me, but it's doesn't seem to be a big deal in practice.
Re: How can C Programs be so Reliable?
#7The thing about C is that you are generally very aware of the side effects. Aside from the libraries you use, the (data) structures are yours. When you set something to NULL, you know damn well that that means to you. As the author alludes to as well - in C you're made more aware of the error conditions you can handle and the ones you can't. So you can code to a level of robustness... Exceptions in Java are all well…
"As the author alludes to as well - in C you're made more aware of the error conditions you can handle and the ones you can't."
You mean like when a function silently returns -1 to indicate failure and then you wonder why your program returned a wrong result (if you're lucky enough to even notice)? In the bigger part of most of my programs I want a big, flashy, loud, total failure by default if anything goes wrong.
Re: How can C Programs be so Reliable?
#8The thing about C is that you are generally very aware of the side effects. Aside from the libraries you use, the (data) structures are yours. When you set something to NULL, you know damn well that that means to you. As the author alludes to as well - in C you're made more aware of the error conditions you can handle and the ones you can't. So you can code to a level of robustness... Exceptions in Java are all well…
"As the author alludes to as well - in C you're made more aware of the error conditions you can handle and the ones you can't." You mean like when a function silently returns -1 to indicate failure and then you wonder why your program returned a wrong result (if you're lucky enough to even notice)? In the bigger part of most of my programs I want a big, flashy, loud, total failure by default if anything goes wrong.
The only time a function would "silently" return a -1 would be if you're not checking your returns for errors! Functions have return codes for a reason.
Re: How can C Programs be so Reliable?
#9The thing about C is that you are generally very aware of the side effects. Aside from the libraries you use, the (data) structures are yours. When you set something to NULL, you know damn well that that means to you. As the author alludes to as well - in C you're made more aware of the error conditions you can handle and the ones you can't. So you can code to a level of robustness... Exceptions in Java are all well…
"As the author alludes to as well - in C you're made more aware of the error conditions you can handle and the ones you can't." You mean like when a function silently returns -1 to indicate failure and then you wonder why your program returned a wrong result (if you're lucky enough to even notice)? In the bigger part of most of my programs I want a big, flashy, loud, total failure by default if anything goes wrong.
if ((result = foo()) == -1) {
fprintf(stderr, "!$*!$&^!$*!!!!\n");
exit(1);
}Re: How can C Programs be so Reliable?
#10The thing about C is that you are generally very aware of the side effects. Aside from the libraries you use, the (data) structures are yours. When you set something to NULL, you know damn well that that means to you. As the author alludes to as well - in C you're made more aware of the error conditions you can handle and the ones you can't. So you can code to a level of robustness... Exceptions in Java are all well…
"As the author alludes to as well - in C you're made more aware of the error conditions you can handle and the ones you can't." You mean like when a function silently returns -1 to indicate failure and then you wonder why your program returned a wrong result (if you're lucky enough to even notice)? In the bigger part of most of my programs I want a big, flashy, loud, total failure by default if anything goes wrong.
You mean like when a function silently returns -1 to indicate failure and then you wonder why your program returned a wrong result (if you're lucky enough to even notice)?
This is the fault of the programmer who wrote the function, not of the language.