Vfs::Transfer callback argument

[John Spray <jcspray icculus org>]

Hello,

Gnome::Vfs::Transfer::transfer takes an optional argument to a progress
callback.  I've found that when this argument is left out the function
never works, throwing an "operation interrupted" exception whenever it's
called.  I assume that this is because the default callback is always
returning false.

Surely this argument should either be mandatory, or have a default value
that works?

John

1. http://www.gtkmm.org/gnomemm2/reference/html/namespaceGnome_1_1Vfs_1_1Transfer.html#8e5e59fd52067e992502eabdb33d3d60