Blank entry, how do I handle them?

["Jamiil Abduqadir" <jalqadir gmail com>]

Hey folks!
I really don't know what to do to resolve this issue, I have been looking in the Gtkmm documentation and will continue doing so, but I have not found, as yet, anything that would indicate a way to handle what I want do, so here is my problem. In my WindowsXP's application (Gtkmm 2.10 Installer) I have several entry boxes, when the user jumps from one entry box to the other, leaving the entry box blank and then clicking on OK, to retrieve the information, the application suffer a segmentation fault. What I would like to know is if there is a signal that I can catch that will tell me if the user has left the entry box and there check if the user has left it blank.

Thanks in advance

-- 
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