COPY fails to read source file

Hello all:

Using 6.5.3, SuSE 6.4, logged in as 'billb'.

Here are 2 instances of the COPY command;

-----------------------------------------------------------------------------
copy custprofile from '/home/billb/custpr.txt' using delimiters ';';
The result is:
  ERROR: COPY command, running in backend with with effective uid 26, could
  not open '/home/billb/custpr.txt' for reading.  Errno = Permission denied
  (13).
The file looks like
 -rw-r--r--  1 billb   users  58902 May 16  11:45 /home/billb/custpr.txt

----------------------------------------------------------------------------
copy custprofile from '/mnt/DOS_C/sybase/custpr.txt' using delimiters ';';
The result is:
  COPY
The file looks like
 -rwxr-xr-x  1 root    root   58902 May 16  11.56 /mnt/DOS_C/sybase/custpr.txt

---------------------------------------------------------------------------

The second instance gave me the results I wanted, but why did the first
instance fail?  If anything, I would have expected permission denied on the
root owner.  I have had the same results on other ocassions.

What am I missing?

TIA
Bill Barnes

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