Memory Leak in C

What is Memory Leak ? How we can avoid ?

Memory Leak:

http://en.wikipedia.org/wiki/Memory_leak

Memory leak occurs when programmers create a memory in heap and forget to delete it.
Memory leaks are particularly serious issues for programs like daemons and servers which by definition never terminate.

#include <stdlib.h> void f() {    int *ptr = (int *) malloc(sizeof(int));    /* Do some work */    return; /* Return without freeing ptr*/ }

To avoid memory leaks, memory allocated on heap should always be freed when no longer needed.

/* Function without memory leak */

#include <stdlib.h>;

void f()

{

   int *ptr = (int *) malloc(sizeof(int));

   /* Do some work */

   free(ptr);

   return;

}


Memory Leak:

char* str = (char*)malloc(sizeof(char) * 4);
str="abc";



To avoid Memory Leak:

char* str = (char*)malloc(sizeof(char) * 4);
strcpy(str, "abc");
str[3] = '\0';