Type 40: Additional Information Guide

Supplemental values and descriptions for fields in other structures.

Result set and ownership

lazybiosGetType40 returns a lazybiosType40Array_t holding every matching structure. Iterate entries using count. A non-NULL result whose count is zero means the table contains no structure of this type; NULL means the arguments were unusable or an allocation failed. Release the set with lazybiosFreeType40, or assign it to ctx->Type40 and let lazybiosCleanup own it.

Every record carries its own SMBIOS handle and the structure length the firmware reported.

Entry interpretation

Each entry identifies another SMBIOS structure by referenced_handle and a field within that structure by referenced_offset. The optional string can describe the supplemental value. The value is exposed as value_length bytes in value because the SMBIOS specification defines its representation as the same type and size as the referenced field. A zero or invalid string index leaves the optional string field absent. A referenced handle of 0xFFFF is preserved and marked absent. A valid entry can have a zero-length value; in that case value is NULL while its field status remains present.

The parser validates the minimum six-byte entry length and the complete bounds of every declared entry before returning the entry array. If any entry is incomplete, field_status.additional_information_entries remains absent and no partial array is exposed. The encoded entry count remains present when its byte was available.

Ownership

The returned structure array, each entry array, each optional string, and each value byte array are allocated by the parser. Release the complete result with lazybiosFreeType40, or assign it to lazybiosCTX::Type40 and use lazybiosCleanup.

See also

Type 40: Additional Information