This function tries to allocate n bytes of memory. On success it returns a pointer to the memory area, in an out-of-core condition, it returns NULL.
This function tries to allocate n bytes of cleared memory (i.e. memory that is initialized with zero bytes). On success it returns a pointer to the memory area, in an out-of-core condition, it returns NULL.
This function tries to resize the memory area pointed to by p to n bytes. On success it returns a pointer to the new memory area, in an out-of-core condition, it returns NULL. Depending on whether the memory pointed to by p is secure memory or not, gcry_realloc tries to use secure memory as well.