Why does 'fortune' write on the fortunes.dat file?

[Jim Haynes]

On a MtXinu 4.3BSD + NFS system we tried putting the fortune program
and its library on a filesystem that is mounted read only.  Doesn't
work, as the program wants to open the fortunes.dat file read/write.
Before I go digging through the code, does anybody know why and what
it is going to write?
haynes at ucscc.ucsc.edu haynes at ucscc.bitnet ...ucbvax!ucscc!haynes

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