ref: d54bc38234b9ee339dc91b6d0c1d7bec27c4928f
dir: /sys/lib/dist.old/pc/inst/hasmbr/
#!/bin/rc
if(! ~ $#* 1) {
echo 'usage: hasmbr /dev/sdC0/part' >[1=2]
exit usage
}
x=`{xd -b $1 | sed -n '32p;32q'}
if(~ $x(16) 55 && ~ $x(17) aa)
exit ''
exit nope