Section: OpenSSL (3SSL)
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BN_CTX_new, BN_CTX_init, BN_CTX_free - allocate and free BN_CTX structures
void BN_CTX_init(BN_CTX *c);
void BN_CTX_free(BN_CTX *c);
is a structure that holds BIGNUM
temporary variables used by
library functions. Since dynamic memory allocation to create BIGNUM
is rather expensive when used in conjunction with repeated subroutine
calls, the BN_CTX
structure is used.
BN_CTX_new() allocates and initializes a BN_CTX
structure. BN_CTX_init() initializes an existing uninitialized
BN_CTX_free() frees the components of the BN_CTX, and if it was
created by BN_CTX_new(), also the structure itself.
If BN_CTX_start(3) has been used on the BN_CTX,
BN_CTX_end(3) must be called before the BN_CTX
may be freed by BN_CTX_free().
returns a pointer to the BN_CTX
. If the allocation fails,
it returns NULL
and sets an error code that can be obtained by
BN_CTX_init() and BN_CTX_free() have no return values.
are available in all versions on SSLeay
and OpenSSL. BN_CTX_init()
was added in SSLeay 0.9.1b.
- RETURN VALUES
- SEE ALSO