Plan 9 from Bell Labs’s /usr/web/sources/plan9/sys/lib/dist/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