+@findex make-face-bold
+@findex make-face-bold-italic
+@findex make-face-italic
+@findex make-face-unbold
+@findex make-face-unitalic
+@vindex face-frob-from-locale-first
+The work of @code{make-face-bold}, @code{make-face-bold-italic},
+@code{make-face-italic}, @code{make-face-unbold},
+@code{make-face-unitalic} functions is affected by
+@code{face-frob-from-locale-first} variable. If it is @code{nil}, those
+functions first try to manipulate device specific data like X font names
+to obtain the desired font face specification. This may be unsuitable
+in environments using different font face specifications for different
+frames, non-Mule environments in particular.
+
+If the variable is non-@code{nil}, those functions first try to figure
+out whether the face font is the same as one of predefined faces:
+@code{default}, @code{bold}, @code{italic}, @code{bold-italic}. If it
+is the same, then the new face font specification is set to be the same
+as that of a corresponding predefined face. Thus if the predefined face
+is set up properly for different frames, the same will hold for the face
+being changed by the functions. This is the behavior one might desire
+in non-Mule environments mentioned above: face being changed still looks
+right in all frames.
+
+How predefined faces might be set up for different frames in such an
+environments is described in @ref{Face Resources}.
+