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POCan all functions in a thread have access to dynamically allocated memory (heap) even without passing pointer or is it local to a function?
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copied!<p>I have a very basic question and need help. I am trying to understand what is the scope of a dynamically allocated memory (on heap). </p> <pre><code>#include <stdio.h> #include <malloc.h> //-----Struct def------- struct node { int x; int y; }; //------GLOBAL DATA------ //-----FUNC DEFINITION---- void funct(){ t->x = 5; //**can I access 't' allocated on heap in main over here ?** t->y = 6; //**can I access 't' allocated on heap in main over here ?** printf ("int x = %d\n", t->x); printf ("int y = %d\n", t->y); return; } //-----MAIN FUNCTION------ int main(void){ struct node * t = NULL;// and what difference will it make if I define //it outside main() instead- as a global pointer variable t = (struct node *) malloc (sizeof(struct node)); t->x = 7; t->y = 12; printf ("int x = %d\n", t->x); printf ("int y = %d\n", t->y); funct(); // FUNCTION CALLED** return 0; } </code></pre> <p>Here, can I access structure <code>t</code> in <code>funct()</code> even though the memory is allocated in <code>main()</code> without passing argument (pointer to <code>t</code> to <code>function funct</code>) - since heap is common to a thread? What difference will it make if I define <code>struct node * t = NULL</code> outside of <code>main()</code> as a global variable and is there anything wrong with it?</p>

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