Created attachment 390708 [details, diff]
Currently the default filename of output from gnome-screenshot include a colon for the time parameter. This is incompatible with filename convention for at least the following cases; (i) owncloud synchronization (ii) dropbox (iii) accessing a shared folder from windows.
An upstream build exists for this on https://bugzilla.gnome.org/show_bug.cgi?id=740520 and ubuntu has a similar bug for it at https://bugs.launchpad.net/ubuntu/+source/gnome-screenshot/+bug/1054808. The attached patch applies cleanly to gnome-screenshot-3.12.0 replacing colon with - allowing me to synchronize the image folder with my owncloud instance.
Upstream looks to disagree specially with dropping the spaces... could you give some concrete examples to upstream bug too as maybe that could help to get the patch upstreamed at some point?
Please note that this patch does not affect spaces at all, only the colon. The spaces doesn't cause any incompatibility for me and I believe upstream does not want to remove it as it affects e.g. translation.
This patch is now included upstream
+*gnome-screenshot-3.14.0-r1 (03 Feb 2015)
+ 03 Feb 2015; Pacho Ramos <email@example.com>
+ +gnome-screenshot-3.14.0-r1.ebuild, -gnome-screenshot-3.14.0.ebuild:
+ Use dash for time format separator (#531330 by Kristian Fiskerstrand), drop