How is the array stored in memory?

arrays c pointers heap-memory stack-memory
som picture som · May 22, 2012 · Viewed 53.6k times · Source

I have a simple program which initializes an array as:

int a[]={10,20,30,40,50};   
char *p;
p=(char*)a;

Now I want to access the value at each byte through pointer p. For that I need to know: how is the array stored in memory? Is it stored on the stack or the heap?

Answer

Alok Save picture Alok Save · May 22, 2012

An array stores its elements in contiguous memory locations.
If You created the array locally it will be on stack. Where the elements are stored depends on the storage specification.
For Example:
An array declared globally or statically would have different storage specification from an array declared locally. Technically, the where part is implementation defined but usually implementations would use similar usage patterns.

  • A local array will be (usually) created on stack while
  • A global or static array will be (usually) created on bss/data segments and
  • A dynamically created array will be created on heap.

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