+.TP 8
+.B \-esc
+When the user types a key with the Alt or Meta keys held down, send an
+ESC character first. This is the default.
+.TP 8
+.B \-meta
+When Meta or Alt are held down, set the high bit on the character instead.
+.TP 8
+.B \-del
+Swap Backspace and Delete. This is the default.
+.TP 8
+.B \-bs
+Do not swap Backspace and Delete.
+.TP 8
+.B \-fps
+Display the current frame rate and CPU load.
+.SH TERMINAL EMULATION
+By default, \fIphosphor\fP allocates a pseudo-tty for the sub-process to
+run under. This has the desirable side effect that the program will be
+able to use
+.BR ioctl (2)
+to fetch information about terminal parameters and window size, which
+many programs (such as
+.BR top (1))
+need to run properly. \fIphosphor\fP will also set the environment
+variable \fITERM\fP to \fIvt100\fP in the child process.
+
+Any characters typed on the phosphor window will be passed along to
+the sub-process. (Note that this only works when running in "window"
+mode, not when running in \fI\-root\fP mode under xscreensaver.)