BN_CTX_NEW(3)              Library Functions Manual              BN_CTX_NEW(3)

NAME
     BN_CTX_new, BN_CTX_free - allocate and free BN_CTX structures

SYNOPSIS
     #include <openssl/bn.h>

     BN_CTX *
     BN_CTX_new(void);

     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_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().  If c is a NULL pointer, no action occurs.

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).

SEE ALSO
     BN_add(3), BN_CTX_start(3), BN_new(3)

HISTORY
     BN_CTX_new() and BN_CTX_free() first appeared in SSLeay 0.5.1 and have
     been available since OpenBSD 2.4.

Linux 6.8.2-arch2-1             April 25, 2023             Linux 6.8.2-arch2-1