Re: Date conversion technique, alpha to Numeric

Barbara Morris wrote:

Jerry Adams wrote:

My understanding is that the date is stored on disk in a binary format,
and that it retains the same value regardless of the what DATFMT's value
is.  That is, one program would have DATFMT(*ISO) and another program
could have DATFMT(*USA) against the same table and that it is merely the
presentation, say on a report or display, that differs.

The fact that it is stored on disk in binary format is irrelevant for
program access.

From a programming point of view, a date variable is always formatted.

If you do DSPPFM, you will see the date as the program sees it.  With
RPG, because of the way I specs work, you can define your internal
program field with any date format you like (say *ISO), but the
_external_ format in the file will always be the same for that
particular date field(say *MDY).  If your internal format is different
from the external format, RPG will do a conversion for you, but it's not
a conversion from a 4-byte binary to your *ISO program format, it's a
conversion from the file's *MDY format to your *ISO program format.

The conversion from 4-byte binary to the file's *MDY format happens
somewhere deep down in the operating system, where the system prepares
the data buffer.