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Control Flow

2 (2.2%)

Arrays, Strings, Pointers, and References

8 (9%)

Functions

4 (4.5%)

Basic object-oriented programming

30 (33.7%)

A bit more advanced OOP (Composition, Operator overloading, Inheritance, Virtual Functions)

18 (20.2%)

Templates

8 (9%)

Other (Explain)

4 (4.5%)

Working with files?  (Streams)

15 (16.9%)

Total Members Voted: 89

[ILikePie]

Uhm, I'm pretty sure nobody develops for this 50 year old machine I have stashed in the basement anymore. From what I've seen, most modern machines have at least three compilers available.

[lordnincompoop]

Okay, simply put: How do I pass a charstar array between functions?

Simply put I wouldn't. Assuming you are trying to pass an array of strings I'd pass a const boost::array<std::string> reference.

However to answer your question.

function(const char*[10]) as 10 is the size of the array of pointers should work fine.

Depending on your compiler you might also be able to use function(const char**) for a multidimensional array of chars, but as you know it's 10 there is no need for this.

I need the function called to pass the charstar array to the "host", or the function that called it.

Or am I just taking the wrong approach?

[Virex]

You'll want to return a pointer to a char array. Just give it the char* you need as the return parameter and be sure to adjust your function definition to (I think) char*. Make sure that the calling function is expecting a char* and not a char[] or your compiler's going to throw a fit.

[eerr]

a pointer to an array of char pointers:

*((char[])*)


voila.

[lordnincompoop]

a pointer to an array of char pointers:

*((char[])*)


voila.

After the function ends, won't the charstararray disappear, causing the pointer pointing to it become a NULL pointer?

Gee, I'm confused. 

[eerr]

Eh, I had to make the post twice, I forgot the part about,

*((char[])*) x;

x=(*((char[length])*)) malloc(sizeof(char)*length);

return x;

[lordnincompoop]

Wait, isn't it *((char*)[]) ?

Blarg, I'll trust you to know this better than me. But can you explain what you just did, so I can use it? 

[Rose]

char**

sheesh.

[lordnincompoop]

char**

sheesh.

Would work if the variable was a simple charstar.

[Rose]

char** is a pointer to a pointer to a char.

it's used for acessing something like:

{{a,b,c,d},{e,f,g,h,},[i,j,k,l}}

[Normandy]

char** and char*[] are both correct in forming an array of strings of variable length. char[]* would form an array of strings of constant length, but the memory would not go out of scope, as you fear. char[][] is the only thing that would go out of scope.

Even then, if you passed the return value to another char[][], the data would be copied. Only if you return from a char[][] to char** would the memory go out of scope.

But really you should at least be using std::vector<std::string> if you really don't want to use boost. Learn STL. It makes your life so much easier.

[Shades]

But really you should at least be using std::vector<std::string> if you really don't want to use boost. Learn STL. It makes your life so much easier.

This or boost::array<std::string>

Only stick with the c strings if your forced to for some reason.

(also i'd recommend stlport as the version of stl you use, but most (all?) standard c libraries come with an implementation these days)

[Supermikhail]

Can anybody with Linux experience help me?
As far as I can figure (and I've been figuring for a long time), when I run my program through the IDI, it creates a file in the directory the executable is in, but when I run it through the terminal, it creates a file in my home directory. Full path, as I first thought, doesn't suit me, because I'd like to distribute the program.
Actually, not only people with Linux experience. If I compile it on Windows, will it do this to me, too?

[eerr]

char**

sheesh.

Japa is right.

I guess I was getting all excited about the catch where "order of operations" applies to variable declarations.

Just forget what I said.

I haven't used C in awhile.

[ILikePie]

Can anybody with Linux experience help me?
As far as I can figure (and I've been figuring for a long time), when I run my program through the IDI, it creates a file in the directory the executable is in, but when I run it through the terminal, it creates a file in my home directory. Full path, as I first thought, doesn't suit me, because I'd like to distribute the program.
Actually, not only people with Linux experience. If I compile it on Windows, will it do this to me, too?

If you want to create files in a local directory use "./file". In C it would look like this `FILE* file = fopen("./file", "wr");`. Should work in Windows too.

e, How are you running it? Do you `cd /path/to/executable; ./exe` or do you run `/path/to/executable/exe`? The files will be created where the user is (ie, the output of pwd), not where the executable is.