Possible bug in fseek/fseeko/lseek modules on MinGW

[Martin Lambers]

Hi,

a user reported a bug in the MinGW version of mpop. After narrowing the
problem down, it seems that after 'fseek(f, 0, SEEK_SET)' is called for
a file 'f' that was opened in mode "r+", subsequent attempts to write to
'f' (e.g. with fprintf) will fail on MinGW when the gnulib fseek module
is in use. The fseek module uses the fseeko module, which in turn uses
the lseek module.

Disabling these modules (using --avoid) fixed the problem for the
reporter. I currently do not have access to a Windows system to
investigate this further myself.

Martin