In Motif 1.1, the first font in widget's font list is the default character set for that widget. If the widget does not have a
font list, it uses a default character set referred to by the constant XmSTRING_DEFAULT_CHARSET. If the user has
set the LANG environment variable, its value is used for this character set. If this value is invalid or its associated font
cannot be used, Motif uses the value of XmFALLBACK_CHARSET, which is vendor−defined but typically set to
"ISO8859−1".
For backwards compatibility, Motif 1.2 essentially equates XmFONTLIST_DEFAULT_TAG with
XmSTRING_DEFAULT_CHARSET when it cannot find an exact match between a compound string and a font list.
XmFONTLIST_DEFAULT_TAG in a compound string or font list matches the tag used in creating a compound string
or specifying a font list entry with the tag XmSTRING_DEFAULT_CHARSET. Some Motif widgets define font list
resources that allow them to provide a consistent appearance for all of their children. In Motif 1.2, the VendorShell
widget defines the XmNbuttonFontList, XmNlabelFontList, and XmNtextFontList resources, while the
MenuShell defines XmNbuttonFontList and XmNlabelFontList. These resources apply to all of the buttons,
Labels, and Text widgets that are descendents of the widget. In Motif 1.1, the VendorShell and MenuShell only
defined the XmNdefaultFontList resource; this resource applied to all of the children of the widget. For
backwards compatibility, if one of the more specific font list resources is not set, its value ...