I have some code in C++ that uses an std::vector of std::strings to store an array of strings. I need to convert it into C. I thought that I would just create c versions of the functions I need (vector.back,vector.push_back,string.operator+=) but am getting lost in the double pointers. Can anybody lead me on the right track here?

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std::vector and std::string do a lot of work internally. You'd probably be better off converting the 'what' instead of the 'how'. Ask yourself what the code is trying to accomplish and write C code to do it.

I was thinking of rather than storing a char** to store a single char* string with some delimiting character. I really need a dynamic array of strings so I do not see any other choice.

You're focusing too much on the 'how'. Explain what the program does and someone can help make suggestions.

Consider why you must convert to C. I cont see many reasons where C would be necessary over C++.

It's not all that difficult to do. Here's an example of push_back

const int BlockSize = 10; // allocate this number of elements at one time
int MaxArraySize = 0; // initial size of the array
int CurrentSize = 0; // current number of elements used in the array

char** array = 0; 

void ReallocArray()
{
   MaxArraySize += BlockSize;
   array = realloc(array,MaxArraySize);
}

char* push_back(const char* item)
{
    if( (CurrentSize+1) >= MaxArraySize )
    {
       ReallocArray();
    }
    array[CurrentSize] = malloc(strlen(item)+1);
    strcpy(array[CurrentSie], item);
    ++CurrentSize;
}
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