Subj:  need help			Section: Psion Programming
  To:  Chris Hennings, 100010,511	Sunday, 02 July, 1995 8:42:05 PM
From:  ROGERIO BRAVO, 100662,2624	#158867

I really hope you donīt minde: I had to post the answer in the news group;
Thank you very much for your help; yhnks to you, now I am spending less
time with calculations; the following is the corresponding to the INTERNET
post I sended. Best regards and I hope someday to be of some assistence.

From: rbravo@telepac.pt (Rogerio Bravo)
Newsgroups: comp.sys.psion
Subject: OPL problem/program: solved at last!
Date: 2 Jul 1995 20:31:51 GMT
Message-ID: <3t6vnn$pb6@tpone.telepac.pt>

Some days ago I asked for help about a problem on programing with OPL;

The problem was:

I wanted to input a date, add a number of days to that date and
obtain the final result: the new date minus 8 days.

In case anybody wants to know how to solve it here it goes:

Chris Hennings (CompuServe 100010,511) help me out with his message:

"If you're happy working in the period 1970 - 2155 then no problems:

y%=1995, mo%=6, d%=28, h%=0, mi%=0, s%=0, yd%
ts&=DATETOSECS(y%,mo%,d%,h%,mi%,d%)      /* This gets seconds since 
1/1/70 is s& */
nodays&=90
nodays&=nodays& * 86400                                          /* To 
get the day offset in seconds          */
ts&=ts&+nodays&                             
SECSTODATE ts&,y%,mo%,d%,h%,mi%,d%,yd%     /* Converts secs back to 
y%.mo% etc */

If you want to work prior to 1970 then you have to do a bit more yourself 
but I've got some code that does this somewhere.

Rgds
Chris"

Whit his answer I was able to produce what I call the final code:

PROC presc:
local y%,mo%,d%,h%,mi%,s%,yd%
local deadline&,ndays&,ts&
h%=0
mi%=0
s%=0
print "Initial Date:"
print "Year:"
input y%
print "Month:"
input mo%
print "Day:"
input d%
print "Number of days:"
input ndays&
ts&=DATETOSECS(y%,mo%,d%,h%,mi%,s%)
ndays&=(ndays&-8)*86400
ts&=ts&+ndays&
SECSTODATE ts&,y%,mo%,d%,h%,mi%,s%,yd%
print
print "Final date:", y%,mo%,d%
get
ENDP

I hope it can be useful to somebody.