in the expression from being interpreted by the shell. Note that it
is possible to apply different constraints to incoming and outgoing
packets using the \fBinbound\fR and \fBoutbound\fR qualifiers. This
in the expression from being interpreted by the shell. Note that it
is possible to apply different constraints to incoming and outgoing
packets using the \fBinbound\fR and \fBoutbound\fR qualifiers. This
-option is currently only available under NetBSD, and then only if both
-the kernel and pppd were compiled with PPP_FILTER defined.
+option is currently only available under NetBSD or Linux, and then
+only if both the kernel and pppd were compiled with PPP_FILTER defined.