- malloc()
- The malloc() function is used to allocate the memory during the execution of the program.
- It does not initialize the memory but carries the garbage value.
- It returns a null pointer if it could not be able to allocate the requested space.
Syntax - ptr = (cast-type*) malloc(byte-size) // allocating the memory using malloc() function.
- calloc()
- The calloc() is same as malloc() function, but the difference only is that it initializes the memory with zero value.
Syntax - ptr = (cast-type*)calloc(n, element-size);// allocating the memory using calloc() function.
- realloc()
- The realloc() function is used to reallocate the memory to the new size.
- If sufficient space is not available in the memory, then the new block is allocated to accommodate the existing data.
Syntax
- ptr = realloc(ptr, newsize); // updating the memory size using realloc() function.
In the above syntax, ptr is allocated to a new size.
free():The free() function releases the memory allocated by either calloc() or malloc() function.
Syntax
free(ptr); // memory is released using free() function.
The above syntax releases the memory from a pointer variable ptr.