Mainframe, MVS and zOS Discussion

Hi All,

I am new to UNIX and shell service. I would like to know if we can define a VSAM file in Unix? And it will work similar way as in zOS environment? If it is not so then what is equivalent to VSAM KSDS on UNIX side?

I would like to know if we can define a VSAM file in Unix?

NO

And it will work similar way as in zOS environment?

NOT applicable

If it is not so then what is equivalent to VSAM KSDS on UNIX side?

NO equivalent

VSAM data sets (only Unix has files on a system z) can ONLY be defined by IDCAMS which is not a Unix utility.  VSAM data sets can be used in Unix System Services by a COBOL program, but it requires the program reference the VSAM data set through a DD name (which is distinctly not a Unix concept).
And VSAM data sets can be sequential (ESDS), relative (RRDS), keyed (KSDS) or linear -- which do you mean?  Sequential files in Unix System Services are different from ESDS but work in the same way.  The others don't have good equivalents in any Unix.

Thanks Robert.

I know some unix so initially I was thiking about an ESDS dataset; I should have made it clear in my first post. So basically there is just no equivalent but the "sequential file for unix" is equivalent to ESDS and for that matter sequential files too, right? (QSAM)

We are thiking to replicate an existing application in unix, that's why I am asking these questions...

Well, as usual, it depends.  If the ESDS has an alternate index defined on it, it is NOT the equivalent of a sequential data set.

Thanks Robert.