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
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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?

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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

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