ref: 8de9a4a06d6d5cc8246464f3835cfe885cf6efcc
dir: /bin/r/
#!/bin/rc rfork e x=1 if(! ~ $#* 0) x=$1 awk -v 'x='^$x ' /^; /{ a[++n] = NR } END { cmd = a[n-x]","a[n-x+1]-1"d;"NR"d" system("sed \''" cmd "\'' /dev/text >/tmp/a; mv /tmp/a /dev/text") }' /dev/text