No, you've to choose it as your default window manager using xwmconfig or manually editing your .xinitrc file. (The first will be ok).
The run: startx
Edit: Since you installed from source you won't have a selection in xwmconfig for it, so edit a file called .xinitrc in your home directory (doesn't exist by default, just create it) and put something like:
Code:
#!/bin/sh
userresources=$HOME/.Xresources
usermodmap=$HOME/.Xmodmap
sysresources=/usr/X11R6/lib/X11/xinit/.Xresources
sysmodmap=/usr/X11R6/lib/X11/xinit/.Xmodmap
# merge in defaults and keymaps
if [ -f $sysresources ]; then
xrdb -merge $sysresources
fi
if [ -f $sysmodmap ]; then
xmodmap $sysmodmap
fi
if [ -f $userresources ]; then
xrdb -merge $userresources
fi
if [ -f $usermodmap ]; then
xmodmap $usermodmap
fi
exec startfluxbox
The run startx.
Oh and If you're wondering why you have to do this, it's because the Window Manager runs inside X, with startfluxbox you're trying to start it but you're not in X. startx command runs a X server and loads first a ~/.xinitrc to execute the window manager. If it can't find it, it looks at /etc/X11/xinit/xinitrc, this is the global window manager option.