stdlib.h
Next time try the built-in help/manual before asking.
malloc/calloc/realloc will return NULL
alloc is used as header file while using malloc and calloc functions in C prog.The definition of malloc function is in the alloc.h file.It's stdlib.h to be more precise
In C, malloc is used to reserve a predetermined size of memory. void * malloc ( size_t size ); calloc is used to reserve a chunk of memory large enough to store num elements, each of a predetermined size. void * calloc ( size_t num, size_t size ); To create a char array of size 10 you can do it in one of two ways: char* mChars = malloc( 10 * sizeof(char) ); char* cChars = calloc( 10, sizeof(char) ); There is no concept of malloc or calloc in Java.
malloc or calloc
The malloc function is one of a group of memory allocation functions; malloc, calloc, realloc, and free. Specifically malloc (size) returns a pointer to a new memory block of at least size bytes, suitably aligned for optimum access for any basic type, or it returns a NULL if the request cannot be satisfied.
free() is a function used to free the memory allocated dynamically ,by both malloc and calloc functions. free(ptr): ptr is a pointer to a memory block which has already been creeated by malloc or calloc.
malloc/calloc/realloc will return NULL
malloc()
alloc is used as header file while using malloc and calloc functions in C prog.The definition of malloc function is in the alloc.h file.It's stdlib.h to be more precise
In C, malloc is used to reserve a predetermined size of memory. void * malloc ( size_t size ); calloc is used to reserve a chunk of memory large enough to store num elements, each of a predetermined size. void * calloc ( size_t num, size_t size ); To create a char array of size 10 you can do it in one of two ways: char* mChars = malloc( 10 * sizeof(char) ); char* cChars = calloc( 10, sizeof(char) ); There is no concept of malloc or calloc in Java.
malloc or calloc
What calloc does is: void *calloc (size_t s1, size_t s2) { size_t s= s1*s2; void *p= malloc (s); if (p && s) memset (p, 0, s); return p; }
The malloc function is one of a group of memory allocation functions; malloc, calloc, realloc, and free. Specifically malloc (size) returns a pointer to a new memory block of at least size bytes, suitably aligned for optimum access for any basic type, or it returns a NULL if the request cannot be satisfied.
Use the free function to release memory that was previously allocated by malloc, calloc or realloc.
calloc operator,malloc operator
int *p, *q; p = (int*) malloc (100 * sizeof (int)); q = (int*) calloc (100, sizeof (int)); Note that p is left in an uninitialised state whereas q is initialised with the value zero.
1.malloc 2.calloc 3.realloc 4.free