IBM Mainframe Forum

Dear all,

I need clues to read a file from bottom. I tried but I'm struck in this. My code goes like this(Aimed to read the last six records but it didn't obviously it wont)

""EXECIO * DISKR INDD(STEM XEM."
DO IX = XEM.0 TO 6 BY -1 "

.


I'm not able to find how to read the last 6 records of a file. I'm confused to resolve this "DO IX=XEM.0 TO "y" BY -1" I don't know what should be the value of "y". Any suggestions will be helpful.

Regards,
Viswa

Dear all,

I assume it is not possible to read a file in reverse. googled landed in sort finally a way out! Thanks all ..

Wishing you all a very happy and prosperous New year

Regards,
Viswa

just for the sake of proper logic ...
( very basic math ... after all )

since You have everything in a stem ( logically equal to an array )
it should not have been that difficult to conclude that
being N the number of elements of the array
the last K entries go from N-K+1 to N

and ...

will process <backwards>

while

will process <forward>

any recent version of <SORT> should support the SUBSET clause
extracting in quite a sophisticated fashion any number of record

Just a quick correction on terminology - you do not read a file from the 'bottom' but from the end. ISPF may display a file file from top-to-bottom but you conceptually process a file from start-to-end, left-to-right. Weird? Maybe, but after so many years of looking at diagrams of files in books it is strange to think about proessing top-to-bottom when all the diagrams are left-to-right.