/usr/man2/cat.3/BN_CTX_new.3.Z(/usr/man2/cat.3/BN_CTX_new.3.Z)

NAME

       BN_CTX_new, BN_CTX_init, BN_CTX_free - allocate and free BN_CTX struc-
       tures

SYNOPSIS

        #include <openssl/bn.h>

        BN_CTX *BN_CTX_new(void);

        void BN_CTX_free(BN_CTX *c);

       Deprecated:

        void BN_CTX_init(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_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().

       BN_CTX_init() (deprecated) initializes an existing uninitialized
       BN_CTX.  This should not be used for new programs. Use BN_CTX_new()
       instead.

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.

1.0.2t                            2019-09-10                     BN_CTX_new(3)
See also BN_CTX_free(3)
See also BN_CTX_init(3)