Structures (or “structs” in C) allow you to group several related variables and treat them as one unit. They are a mechanism for extending the type system of the C language by introducing user-defined ...

1 typedef struct bignum_st 2 { 3 BN_ULONG *d; /* Pointer to an array 4 'BN_BITS2' bit chunks. */ 5 int top; /* Index of last used 6 d +1. */ 7 /* The next are internal book keeping 8 for bn_expand. */ ...