🚀 go-pugleaf

In article <9006251717.AA10430@moose.informix.com> kwang@moose.UUCP (Kwang Sung) writes:
>We have at least 2 ASN.1 compilers such as ISODE ASN.1 compiler and MAVROS 
>ASN.1 compiler from Germany.  Seems to me I have 2 different results when I 
>compile my ASN.1 module. I thought those were supposed to follow ISO 8824 spec.
>Am I right ?? But I don't know why this happened.  Thanks.
>

I don't know if this is what is happening in your case but it is
possible to produce two different (but correct) encodings from the same
ASN1 source file if each encoder uses the two different types of
length encoding.

Basically there are two types of length encoding. "Definite length
encoding", whereby the "length" part of the asn1 "type-length-contents"
actually specifies the length in octets of the contents octet string.
Or, "Indefinite length encoding", whereby the "length" part does not
contain the length but instead the end of the contents is indicated by
a "00" followed by "00" in the byte stream (sort of like an end-of-file
indicator). A special value in the length part indicates which type of
length encoding is in use.

It may be that one compiler generates encoders which produce definate
length encoded octet strings and the other compiler indefinite. I've a
vague recollection that the ISO-DE compiler will switch from definite
to indefinite if the contents become more than a particular length, maybe
wrong.
			Regards
				Paul.
			

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  /  / /  / /  / /	Paul Davies, STC Telecommunications,
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