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POCan I get a pointer to a struct as a parameter from a function in C?
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copied!<p>I have a type defined like this:</p> <pre><code>struct DynTab_s { int object_count; //other fields void *data; }; typedef struct DynTab_s *Dyntab_t; //note that type I use is pointer to struct </code></pre> <p>I have a storage utility that I can user to store and retrieve them. I've chosen to support int, double and pointer type. I have a function to retrieve the int and double values by key:</p> <pre><code>int MyHashtableGet(MyHashtable_t Hashtable, void *Key, void *Value) { void *Row = NULL; int RetValue = -1; MakeRow(Hashtable, Key, NULL, &Row); if (!MyStoreSelect(Hashtable->TableId, Row)) { switch (Hashtable->ValueType) { case MY_HASHTABLE_TYPE_INT: *(int *)Value = *(int *)((char *)Row + Hashtable->KeySize); break; case MY_HASHTABLE_TYPE_POINTER: //after row below I can see the DynTab_t in the item when I cast it Value = *(void **)*(int **)((char *)Row + Hashtable->KeySize); break; } } MyFree(Row); return RetValue; } </code></pre> <p>that work for int. But not for pointer when I try to get Dyntab_t. This works if I use function</p> <pre><code>void *MyHashtableGetPointer(MyHashtable_t Hashtable, void *Key) { void *Row = NULL; void *RetValue = NULL; MakeRow(Hashtable, Key, NULL, &Row); if (!MyStoreSelect(Hashtable->TableId, Row)) RetValue = *(void **)*(int **)((char *)Row + Hashtable->KeySize); MyFree(Row); return RetValue; } </code></pre> <p>when I call it with:</p> <pre><code>int Key = 1; DynTab_t MyTab; MyTab = (DynTab_t)MyHashtableGetPointer(MyHashtable, &Key); </code></pre> <p>The question is can I at all use this MyHashtableGet to get DynTab_t item or does second parameter have to be void ** type? If yes, can you please provide the exact syntax to call and to MyHashtableGet in case of MY_HASHTABLE_TYPE_POINTER. </p> <p>Thanks & BR -Matti </p>

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