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int init_structure(struct my_structure** s)

{

enum { eAlign = 7 } ;

size_t aligned_size, total_space;

char *base;

aligned_size = ((eAlign+sizeof(struct my_structure)) &(~eAlign));

total_space = aligned_size + sizeof(struct my_substructure);

errno = 0;

base = calloc(total_space,sizeof(*base));

if(!base)

return errno;

*s = (void *)base;

*s->substructure = (void *)(base + aligned_size);

return 0;

}