BIO_F_NULL(3)              Library Functions Manual              BIO_F_NULL(3)

NAME
     BIO_f_null - null filter

SYNOPSIS
     #include <openssl/bio.h>

     const BIO_METHOD *
     BIO_f_null(void);

DESCRIPTION
     BIO_f_null() returns the null filter BIO method.  This is a filter BIO
     that does nothing.  As may be apparent, a null filter BIO is not
     particularly useful.

     All requests to a null filter BIO are passed through to the next BIO in
     the chain: this means that a BIO chain containing a null filter BIO
     behaves just as though the BIO was not there.

     A chain containing a null filter BIO cannot be copied with
     BIO_dup_chain(3), and any attempt to do so fails and returns NULL.

RETURN VALUES
     BIO_f_null() returns the null filter BIO method.

     When called on a null filter BIO object, BIO_method_type(3) returns the
     constant BIO_TYPE_NULL_FILTER and BIO_method_name(3) returns a pointer to
     the static string "NULL filter", not to be confused with a NUL string nor
     with a NULL pointer.

SEE ALSO
     BIO_new(3)

HISTORY
     BIO_f_null() first appeared in SSLeay 0.8.0 and has been available since
     OpenBSD 2.4.

Linux 6.8.2-arch2-1             April 11, 2023             Linux 6.8.2-arch2-1