IriX64@FthrNtr /usr/brlcad/bin
$ ./rt --help
BRL-CAD Release 9.9.9   The BRL-CAD Raytracer RT
    Wed Apr 18 13:50:57 EST 2007, Compilation 102
    IriX64@FthrNtr:/home/IriX64/brlcad-9.9.9/src/rt
BRL-CAD Release 9.9.9   The BRL-CAD Ray-Tracing Library
    Wed Apr 18 13:34:01 EST 2007, Compilation 9
    IriX64@FthrNtr:/home/IriX64/brlcad-9.9.9/src/librt
BRL-CAD Release 9.9.9   The BRL-CAD Numerical Computation Library
    Wed Apr 18 13:32:50 EST 2007, Compilation 7
    IriX64@FthrNtr:/home/IriX64/brlcad-9.9.9/src/libbn
BRL-CAD Release 9.9.9   The BRL-CAD Utility Library
    Wed Apr 18 13:30:52 EST 2007, Compilation 7
    IriX64@FthrNtr:/home/IriX64/brlcad-9.9.9/src/libbu

WARNING: Compile-time debugging is enabled and may limit performance
Running on FthrNtr
./rt:  MGED database not specified
Usage:  rt [options] model.g objects...
Options:
 -s #           Square grid size in pixels (default 512)
 -w # -n #      Grid size width and height in pixels
 -V #           View (pixel) aspect ratio (width/height)
 -a #           Azimuth in deg
 -e #           Elevation in deg
 -M             Read matrix+cmds on stdin
 -N #           NMG debug flags
 -o model.pix   Output file, .pix format (default=fb)
 -x #           librt debug flags
 -X #           rt debug flags
 -p #           Perspective, degrees side to side
 -P #           Set number of processors
 -T #/#         Tolerance: distance/angular
 -r             Report overlaps
 -R             Do not report overlaps

IriX64@FthrNtr /usr/brlcad/bin
$