How can I pass a const array or a variable array to a function in C?

Posted by CSharperWithJava on Stack Overflow See other posts from Stack Overflow or by CSharperWithJava
Published on 2010-06-15T15:15:43Z Indexed on 2010/06/15 15:22 UTC
Read the original article Hit count: 278

Filed under:

I have a simple function Bar that uses a set of values from a data set that is passed in in the form of an Array of data structures. The data can come from two sources: a constant initialized array of default values, or a dynamically updated cache.

The calling function determines which data is used and should be passed to Bar. Bar doesn't need to edit any of the data and in fact should never do so. How should I declare Bar's data parameter so that I can provide data from either set?

union Foo
{
long _long;
int _int;
}

static const Foo DEFAULTS[8] = {1,10,100,1000,10000,100000,1000000,10000000};
static Foo Cache[8] = {0};

void Bar(Foo* dataSet, int len);//example function prototype

Note, this is C, NOT C++ if that makes a difference;

Edit
Oh, one more thing. When I use the example prototype I get a type qualifier mismatch warning, (because I'm passing a mutable reference to a const array?). What do I have to change for that?

Related posts about pointers

C++ smart pointers: sharing pointers vs. sharing data

as seen on Stack Overflow - Search for 'Stack Overflow'
In this insightful article, one of the Qt programmers tries to explain the different kinds of smart pointers Qt implements. In the beginning, he makes a distinction between sharing data and sharing the pointers themselves: First, let’s get one thing straight: there’s a difference between sharing … >>> More
handling refrence to pointers/double pointers using SWIG [C++ to Java]

as seen on Stack Overflow - Search for 'Stack Overflow'
My code has an interface like class IExample { ~IExample(); //pure virtual methods ...}; a class inheriting the interface like class CExample : public IExample { protected: CExample(); //implementation of pure virtual methods ... }; and a global function to create object of this class - createExample(… >>> More
char pointers & integer pointers (++)

as seen on Stack Overflow - Search for 'Stack Overflow'
i have two pointers, char *str1; int *str2; if i look at the size of both the pointers lets assume str1=4 bytes str2=4 bytes str1++ will increment by 1 byte but if str2++ will increment 4 byte could anybody tell e the concept behind this? >>> More
Smart pointers - cases where they cannot replace raw pointers

as seen on Stack Overflow - Search for 'Stack Overflow'
HI, I have this query about smart pointers. I heard from one of my friends that smart pointers can almost always replace raw pointers. but when i asked him what are the other cases where smart pointers cannot replace the raw pointers,i did not get the answer from him. could anybody please tell… >>> More
C++ Pointers: Number of levels of Indirection

as seen on Programmers - Search for 'Programmers'
In a C++ program that doesn't contain legacy C code, is there a guideline regarding the maximum number of levels of indirection that should be used in the source code? I know that in C (as opposed to C++), some programmers have used pointers to pointers for a multiple dimension array, but for the… >>> More

Developer IT

How can I pass a const array or a variable array to a function in C? - Developer IT

How can I pass a const array or a variable array to a function in C?

c

pointers

array

const

immutable

Related posts about c

Related posts about pointers

C++ smart pointers: sharing pointers vs. sharing data

handling refrence to pointers/double pointers using SWIG [C++ to Java]

char pointers & integer pointers (++)

Smart pointers - cases where they cannot replace raw pointers

C++ Pointers: Number of levels of Indirection

Categories cloud