ASN1_NULL_NEW(3)           Library Functions Manual           ASN1_NULL_NEW(3)

NAME
     ASN1_NULL_new, ASN1_NULL_free - ASN.1 NULL value

SYNOPSIS
     #include <openssl/asn1.h>

     ASN1_NULL *
     ASN1_NULL_new(void);

     void
     ASN1_NULL_free(ASN1_NULL *val_in);

DESCRIPTION
     ASN1_NULL_new() returns a specific invalid pointer that represents the
     ASN.1 NULL value, which is the only possible value of the ASN.1 NULL
     type.  That pointer is different from a NULL pointer.  Dereferencing it
     almost certainly results in a segmentation fault.  This function does not
     allocate memory and cannot fail.

     ASN1_NULL_free() has no effect whatsoever.  In particular, it ignores the
     val_in argument and does not free any memory.  In normal use, application
     programs only pass the invalid pointer obtained from ASN1_NULL_new() to
     this function.  But even if a valid pointer is passed, that pointer does
     not become invalid.

     The ASN.1 NULL type is also represented by the V_ASN1_NULL type
     identifier constant.

SEE ALSO
     ASN1_item_new(3), d2i_ASN1_NULL(3)

STANDARDS
     ITU-T Recommendation X.208, also known as ISO/IEC 8824-1: Specification
     of Abstract Syntax Notation One (ASN.1), section 19: Notation for the
     null type

HISTORY
     ASN1_NULL_new() and ASN1_NULL_free() first appeared in OpenSSL 0.9.5 and
     have been available since OpenBSD 2.7.

Linux 6.8.7-arch1-1            December 9, 2021            Linux 6.8.7-arch1-1