Well, I am back, although I have now changed the topic title to "replot".
Like I said before, my ultimate objective is to have a single ps document where, say, pages 1 and 3 are in landscape and page 2 in portrait; that, I can already do with a small script if I have the two original files, one with all pages in landscape and another with all pages in portrait...then, I can pick and choose what pages I want in the final document.
Here is the thing:
I have managed to plot in landscape (no surprise there, that is the default).
I have managed to plot in portrait, for real; the one option that does it is command line argument -portrait, and not plsdiori.
I have also managed to do both things above in a single run by opening two streams, one left alone (landscape) and another set to protrait.  This way I end up with I what need.
So, basically, I am done. 
The thing is that I see a couple of C examples with the plreplot() command and I thought that was a lot more elegant than having to open two streams at the begining, keep switching/plotting to both streams at all times, and closing both streams at the end. Just doing everything once and saving a copy of it at the end seems simpler, if I can change from landscape to portrait right before the replot...except that I couldn't get there, since plreplot() will not work for me from Fortran...curiously enough, there are two C examples that use plreplot() but none in Fortran...does this mean something, i.e., plreplot does not work from fortran?
Here is the message:
plreplot: plot buffer not available

Germán Salazar          Siemens Power Generation                           
Engineering Computing             4400 Alafaya Trail, Q1-202
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