Re: SCAN vs %scan

Chuck -

it is a one-off program for creating address information during a system conversion.

As it reads records from the legacy address book file, the program SCANs for for values in the name field and replace them with other hard-coded values before writing out the address book information to the file which will be imported into the new system.

For example:

C 'Abc ' SCAN PNAME P
C IF P > 0
C MOVEA 'ABC ' PL(P)
C ENDIF

The array named PL redefines the field PNAME.

Perhaps I can better improve the program's performance by replacing the MOVEA with %replace:
Where I have added code in this routine, I have used %replace.

- sjl


On 09-Jan-2012 11:11 , sjl wrote:

has anyone benchmarked speed comparison of using SCAN versus %SCAN?

I inherited and am maintaining a fixed-format RPGIV program which
uses SCAN to scan strings for certain values (hundreds of
occurrences of the SCAN opcode), and I am wondering if I can get any
kind of performance improvement if I change them to use %scan
instead.

Then Chuck wrote:
Perhaps describing more thoroughly what is being accomplished with
the hundreds of SCAN operations and using what data structures, might
allow for responses suggesting even more alternatives for improvements;
i.e. something more than only what might be achieved by using %scan vs SCAN.