1027 was a test case and the data is arbitrary. I think the point of round trip is supposed to be that *every* character is "recoverable."
A good write-up in of all places <g> the Glossary of the Z Unicode manual. Emphasis is mine. Round trip. Encoding that occurs when *every* code point in the source CCSID maps to a unique code point in the target CCSID. Using round trip tables ensure the capability of reversing the conversion, and recovering the complete original source datastream. I'm going to see what they say on the PMR. Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Bill Godfrey Sent: Tuesday, June 12, 2012 7:12 PM To: IBM-MAIN@bama.ua.edu Subject: Re: Anyone a Unicode Services expert? -- roundtrip conversion Maybe it will turn out that "round trip" only applies to the characters that are defined in the Source CCSID (and I'm not sure if "defined" is the right word). When I look at a chart of CCSID 1027 here: ftp://ftp.software.ibm.com/software/globalization/gcoc/attachments/CP01027.p df I see that all of the characters that you see being being converted to X'1A' are either outside the chart (which starts at X'40') or have no identified value in the chart. If your data contains these unidentified characters, what is their purpose, and is it really appropriate to consider the data to be associated with CCSID 1027, or just something related to but not the same as CCSID 1027? Bill On Tue, 12 Jun 2012 16:42:02 -0700, Charles Mills wrote: >Not sure what you mean. Here's the PMR: > >Problem Details >. >Product or Service: Support for Unicode Component ID: 5752SCUNI . >Operating System: z/OS >. >Problem title >Round trip conversion not working as expected . >Problem description >My understanding of "round trip" conversion is that every code point in >the Source CCSID should convert to a unique code point in the Target >CCSID (so that conversion in the reverse direction will restore the >original code points). However, when I use CUNLCNV to convert between >CCSIDs 1027 and 1208 I see more than one character converted to x'1A' >(UTF8 SUB). Is round trip conversion working correctly? (Both the >documentation and CUNLINFO report that 'R' is a supported conversion >technique for these two CCSIDs.) > >Characters converted to X'1A' include 3F, 41, 6A, 80, 90, etc. > >Thank you for your consideration. >. >Business impact ( BusImpact ) >Negatively impacting product design decisions. > >Charles >-----Original Message----- >From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On >Behalf Of Tony Harminc >Sent: Tuesday, June 12, 2012 4:15 PM >To: IBM-MAIN@bama.ua.edu >Subject: Re: Anyone a Unicode Services expert? -- roundtrip conversion > >On 12 June 2012 18:55, Charles Mills <charl...@mcn.org> wrote: >> I have opened a PMR. > >For the doc, or the behaviour of the service? Or did you choose the >"let us decide for you" option...? > >Tony H. > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
