Re: Help regarding C64 Textual Conventiond defined in "Understanding SNMP MIBs - Perkins"
Dave Shield <[email protected]>
| Newsgroups | gmane.network.net-snmp.user |
|---|---|
| Message-ID | <[email protected]> |
[ Please do *NOT* post the same request to multiple mailing lists - particularly with no indication of the fact. Thank you.] On Mon, 2005-10-24 at 23:39 +0800, Kurapati M-G19456 wrote: > My question are > 1. why is the length field is represented as 03 i.e. one byte Because it fits in one byte, presumably. Why waste space? > (2 bytes is reserved for length in Opaque)? Whatever gave you that idea? BER encoding allows the length to be a varying number of bytes. It's potentially *more* than two octets (though in practise, two octets is sufficient). Opaque is no different from any other type, AFAIK. > 2. To represent value of 56782 in hexadecimal it is enough if we > represent by 'ddce'h. No - because the first bit of a BER encoding is the sign bit. The first bit of 'ddce'h is set, which would indicate a negative number. A counter value must be positive. The extra (0) octet is needed to ensure that the sign bit is clear. (You just fell into one of David's traps, methinks!) > 3. Can we use the following tag values for other 64bit data types? > Counter64 9f76, > Signed64 9f7A, > Unsigned64 9f7B. This is a non-standard convention - you can do whatever you like. Almost nothing will understand you, which is a minor disadvantage I suppose. But if you're not worried about talking to yourself, feel free! > Your clarifications towards understanding this C64 textual convention > and data value representation in the Opaque stream will be greatly > appreciated. The most important thing to understand about this convention is that it is not particularly widely supported, and is probably not worth bothering about nowadays. Dave ------------------------------------------------------- This SF.Net email is sponsored by the JBoss Inc. Get Certified Today * Register for a JBoss Training Course Free Certification Exam for All Training Attendees Through End of 2005 Visit http://www.jboss.com/services/certification for more information _______________________________________________ Net-snmp-users mailing list [email protected] Please see the following page to unsubscribe or change other options: https://lists.sourceforge.net/lists/listinfo/net-snmp-users