Provided by: libssl-doc_1.0.1f-1ubuntu2.27_all 

NAME
BN_CTX_new, BN_CTX_init, BN_CTX_free - allocate and free BN_CTX structures
SYNOPSIS
#include <openssl/bn.h>
BN_CTX *BN_CTX_new(void);
void BN_CTX_init(BN_CTX *c);
void BN_CTX_free(BN_CTX *c);
DESCRIPTION
A BN_CTX is a structure that holds BIGNUM temporary variables used by library functions. Since dynamic
memory allocation to create BIGNUMs 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.
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().
RETURN VALUES
BN_CTX_new() returns a pointer to the BN_CTX. If the allocation fails, it returns NULL and sets an error
code that can be obtained by ERR_get_error(3).
BN_CTX_init() and BN_CTX_free() have no return values.
SEE ALSO
bn(3), ERR_get_error(3), BN_add(3), BN_CTX_start(3)
HISTORY
BN_CTX_new() and BN_CTX_free() are available in all versions on SSLeay and OpenSSL. BN_CTX_init() was
added in SSLeay 0.9.1b.
1.0.1f 2014-01-06 BN_CTX_new(3SSL)