+# Open a dialog box which asks the user to input a text
+#
+# Usage: gsu_input_box <text> <init>
+#
+# <text> is displayed above of the input field, which is is preset to <init>.
+# The entered text is returned in $result. On success (user pressed OK)
+# the function returns zero. If the user selected Cancel, the return value is
+# one. On dialog errors, a negative error code is returned.