topic Unpacking Packed COMP-3/binary data from Mainframe in Operating System - HP-UX

Unpacking Packed COMP-3/binary data from Mainframe

Vinayak Shet — Fri, 15 Nov 2002 23:08:32 GMT

Hi All,
I have a Mainframe file which has the following format

f1f2p1p2f3
where f1,f2,f3 are simple charater data
and p1,p2 are packed data in COMP-3 format

My task is to get this file on Unix and unpack the packed data using any C routine or anything else so that I can create a new file with the character fields remaining as it is and the packed data unpacked to ascii format.

Can anyone help me with this.

Thanks,
Vinayak

Re: Unpacking Packed COMP-3/binary data from Mainframe

James R. Ferguson — Fri, 15 Nov 2002 23:33:26 GMT

Hi:

I'd unpack the file *on* the mainframe into a new file which is then ftp'd as character data to the Unix server.

If necessary use 'dd' to unblock and convert EBCDIC to ASCII. See the man pages for 'dd' for more information.

Regards!

...JRF...

Re: Unpacking Packed COMP-3/binary data from Mainframe

Vinayak Shet — Sat, 16 Nov 2002 19:48:14 GMT

We can't unpack the file on the mainframe side since we dont have a resource to do it. Thats the reason we have to first bring the file on Unix and then unpack the packed comp-3 fields.

Do you know of any routine in C whic will unpack the COMP-3 packed data.

Thanks,
Vinayak

Re: Unpacking Packed COMP-3/binary data from Mainframe

John Poff — Sat, 16 Nov 2002 21:00:53 GMT

Hi,

Here is a link to a page that talks about handling COMP3 binary data. The page agrees with what James said, that it is better to try to unpack the field on the mainframe side, but if you can't do that they have some sample Java code to try to unpack a COMP3 field.

http://www.room42.com/store/computer_center/packed_decimal.shtml

Good luck!

JP