Hello trid users,
some days ago i run TrID on hundreds of ar-archives and libraries
described in general by ark-ar-archiver.trid.xml as "ar
archive". ( see appended output/trid-old.txt)
On newest Wikipedia site about "Ar (Unix)" a 64-bit variant for System
V libraries is mentioned. This is matched by examples like
lib64ext2fs-nopic.a described in this text. So i add to new
lib-ar-svr64.trid.xml definition wikipedia page as reference by line:
<RefURL>
https://en.wikipedia.org/wiki/Ar_(Unix)</RefURL>
In this variant for symbol lookup table the the string "/SYM64/"
instead "/" is used as identifier. Together with magic for
ar-archives in System V filename notation this is now described by
XML construct:
<Bytes>213C617263683E0A2F53594D36342F202020202020202020</Bytes>
<ASCII> ! . a r c h . . / S Y M 6 4 / </ASCII>
<Pos>0</Pos>
With the tool ar, the libraries content can be unpacked. This is now
described by line:
<Mime>application/x-archive</Mime>
The unpacking gives object files (*.o) described by other trid
definitions like exe-elf.trid.xml as "ELF Executable and Linkable
format (generic)". The file command { see
https://en.wikipedia.org/wiki/File_(command)} described the object
file as "ELF 64-bit MSB relocatable, MIPS,..." or "ELF 32-bit MSB
relocatable, MIPS,..." ( see appended output/file.txt ).
I only inspected a few samples for mips system. There is only found
".a" as file name extension. This is expressed by line:
<Ext>A</Ext>
But i do not know if this is true for all such libraries.
With new trid definition all inspected 64-bit libraries are now
described ( see appended output/trid-new.txt) more precisely . TrID
definition, some examples and output are stored in archive
svr64.zip. I hope that the XML file can be used in future version of
triddefs.
There exist more variants of ar libraries (BSD etc. ). I am
working on these items and will generate more trid definitions.
With best wishes
J?rg Jenderek
