Why does / change size with mail?

[Terence P. Ma]

Hope the title isn't too obscure ... anyway (question I didn't find in one
of my FMs, please tell me which one it's in.  Also didn't find it in FAQs).

I came back from 2 weeks of business trips to 2.3 MBytes worth of mail (I
get several newsgroups as email because I don't have Usenet up and running
yet on my system).  I also noticed when I did a "df" that my "/" was up at
about 85% used.  As I emptied my mailbox, a "df" returned that my "/" was
back to a more normal 62% used.  The difference seemed to be the size of my
mailbox.

However, my mailbox is in /usr/spool/mail which is in "/usr", a separately
mounted partition (and thus shouldn't affect "/").  I thought that maybe it
was because when I was using mailtool (SunOS4.1.1; SS1+; OpenWindows) a file
containing the full mailbox was being kept in "/tmp" which uses up "/"
space, but there is no use of "/tmp" at the time.

Could someone please explain this phenomenon to me?

Thanks in advance!
Tere

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Terence P. Ma, Ph.D.				
Department of Anatomy				If it were easy, some one
University of Mississippi Medical Center	would have done it already.
2500 North State Street					-- anonymous
Jackson, MS 39216				
VOICE:	601-984-1654			UUCP:	tpm-sprl!tpm at uunet.uu.net
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