sector-write

#!/bin/bash

dev=
offset=0
in=

darg () {
	if [ -z "$dev" ]; then dev="$1"; else out="$1"; fi
}

usage()
{
	echo "Usage: $0 [DEVICE] [SECTOR] INFILE"
	echo "  DEVICE has the form \"osprd*\" and defaults to \"osprda\""
	echo "  SECTOR is the sector number and defaults to 0"
	echo "  INFILE is the file to copy to the device"
	exit 1
}

while [ $# -ne 0 ]
do
	arg=$1
	shift
	case "$arg" in
		-h | --help)
			usage
			;;
		osprd[abcd])
			darg "/dev/$arg"
			;;
		/dev/*)
			darg "$arg"
			;;
		[0-9]*)
			offset="$arg"
			;;
		*)
			in="$arg"
			;;
	esac
done

if [ -z "$in" -a -t 0 ]; then
	echo "sector_write: Refusing to read from terminal!  Supply a filename or '-'." 1>&2
	exit 1
fi

[ -z "$dev" ] && dev=/dev/osprda
ifarg="if=$in"; [ "$in" = '-' -o "$in" = '/dev/stdin' -o -z "$in" ] && ifarg=
ofarg="of=$dev"; [ "$dev" = '-' -o "$dev" = '/dev/stdout' ] && ofarg=

if [ -z "$in" ]
then
	echo "Error: Must provide input file"
	usage
else
	dd $ifarg $ofarg bs=512 count=1 seek=$offset
fi