debian man page for bn_clear_free

BN_new(3SSL)							      OpenSSL							      BN_new(3SSL)

NAME
       BN_new, BN_init, BN_clear, BN_free, BN_clear_free - allocate and free BIGNUMs

SYNOPSIS
	#include <openssl/bn.h>

	BIGNUM *BN_new(void);

	void BN_init(BIGNUM *);

	void BN_clear(BIGNUM *a);

	void BN_free(BIGNUM *a);

	void BN_clear_free(BIGNUM *a);

DESCRIPTION
       BN_new() allocates and initializes a BIGNUM structure. BN_init() initializes an existing uninitialized BIGNUM.

       BN_clear() is used to destroy sensitive data such as keys when they are no longer needed. It erases the memory used by a and sets it to the
       value 0.

       BN_free() frees the components of the BIGNUM, and if it was created by BN_new(), also the structure itself. BN_clear_free() additionally
       overwrites the data before the memory is returned to the system.

RETURN VALUES
       BN_new() returns a pointer to the BIGNUM. If the allocation fails, it returns NULL and sets an error code that can be obtained by
       ERR_get_error(3).

       BN_init(), BN_clear(), BN_free() and BN_clear_free() have no return values.

SEE ALSO
       bn(3), ERR_get_error(3)

HISTORY
       BN_new(), BN_clear(), BN_free() and BN_clear_free() are available in all versions on SSLeay and OpenSSL.  BN_init() was added in SSLeay
       0.9.1b.

1.0.1e								    2013-02-11							      BN_new(3SSL)