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Programming
Segmentation fault when I pass a char pointer to a function in C.
Post 303016223 by dryden on Sunday 22nd of April 2018 11:34:51 AM
04-22-2018
Yes, I knew most of that. After all, I have Java experience (just kidding).
Well I knew most of that (except the history) -- I didn't know that once it was different.
It's difficult to assess because "segmentation fault" is really about the only error message you ever get :-/.
I'm lucky to know it means "page fault" -- the first time it happened to me I had to think about what it could mean and then I figured it must be read only,
lately I found out that the "const" keyword does about the same thing, but only on the compiler level this time -- but I'm changing the subject a bit I guess
.
Yes, but I often think "An array is a pointer" to remember that I shouldn't use &array to get its address.
But I'm happy to learn this workaround, although I prefer to use strdup("string") instead..... although.... and strdupa also has its own caveats.
Funnily, in Java Strings are also immutable, and you have to use StringBuffer (or StringBuilder) instead to change them. Because of that reason, porting from C to Java is sometimes less strange than you would expect.
I'm actually quite interested to start using that garbage collector though (libgc1c2), although the number of applications (on Linux) that actually uses it is rather limited, only Inkscape depends on it on my system.
Anyway, enough.
Well I knew most of that (except the history) -- I didn't know that once it was different.
It's difficult to assess because "segmentation fault" is really about the only error message you ever get :-/.
I'm lucky to know it means "page fault" -- the first time it happened to me I had to think about what it could mean and then I figured it must be read only,
lately I found out that the "const" keyword does about the same thing, but only on the compiler level this time -- but I'm changing the subject a bit I guess
.Yes, but I often think "An array is a pointer" to remember that I shouldn't use &array to get its address.
But I'm happy to learn this workaround, although I prefer to use strdup("string") instead..... although.... and strdupa also has its own caveats.
Funnily, in Java Strings are also immutable, and you have to use StringBuffer (or StringBuilder) instead to change them. Because of that reason, porting from C to Java is sometimes less strange than you would expect.
I'm actually quite interested to start using that garbage collector though (libgc1c2), although the number of applications (on Linux) that actually uses it is rather limited, only Inkscape depends on it on my system.
Anyway, enough.
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