On Sun, 15 Aug 2010 20:01:49 -0500, Joel C. Ewing wrote: > >The point of Shmuel's comment, of course, is that the one most common, >unavoidable-in-MVS place where dates of the form yyddd were in >wide-scale use was in SMF accounting records. The format there is >packed-decimal, so hex digits are out. The old format was actually >+00yyddd, where the 00 was reserved, so the one and only way to preserve >the packed decimal representation and also preserve the existing >relationship that the representation for the next year is current year + >1 (in base 10) was to go with 2000-01-01 == 0100001, which is what IBM >did. For those who were already converting SMF dates into a four-digit >year via 00yyddd + 1900000, this extension was so compatible that it >wasn't even necessary to make any code changes for Y2K! > Thanks. I had been unfamiliar with the format of SMF data.
Which still leaves me wondering why, if they used 4-byte packed decimal, they didn't from the very beginning place the century ratner than 00 in the left byte, making the conversion to a 4-digit year even simpler by one addition? -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
