43 lines
625 B
Go
43 lines
625 B
Go
package main
|
|
|
|
import (
|
|
"flag"
|
|
"fmt"
|
|
"os"
|
|
"syscall"
|
|
"unsafe"
|
|
)
|
|
|
|
// See https://github.com/benmcclelland/mtio
|
|
const (
|
|
MTIOCPOS = 0x80086d03 // Get tape position
|
|
)
|
|
|
|
// Position is struct for MTIOCPOS
|
|
type Position struct {
|
|
BlkNo int64 // Current block number
|
|
}
|
|
|
|
func main() {
|
|
file := flag.String("file", "/dev/nst0", "File of tape drive to open")
|
|
|
|
flag.Parse()
|
|
|
|
f, err := os.OpenFile(*file, os.O_RDONLY, os.ModeCharDevice)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
defer f.Close()
|
|
|
|
pos := &Position{}
|
|
|
|
syscall.Syscall(
|
|
syscall.SYS_IOCTL,
|
|
f.Fd(),
|
|
MTIOCPOS,
|
|
uintptr(unsafe.Pointer(pos)),
|
|
)
|
|
|
|
fmt.Println(pos.BlkNo)
|
|
}
|