47 lines
815 B
Go
47 lines
815 B
Go
package main
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import (
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"flag"
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"os"
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"syscall"
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"unsafe"
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)
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// See https://github.com/benmcclelland/mtio
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const (
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MTIOCTOP = 0x40086d01 // Do magnetic tape operation
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MTSEEK = 22 // Seek to block
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)
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// Operation is struct for MTIOCTOP
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type Operation struct {
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Op int16 // Operation ID
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Pad int16 // Padding to match C structures
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Count int32 // Operation count
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}
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func main() {
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file := flag.String("file", "/dev/nst0", "File of tape drive to open")
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record := flag.Int("record", 0, "Record to seek too")
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flag.Parse()
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f, err := os.OpenFile(*file, os.O_RDONLY, os.ModeCharDevice)
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if err != nil {
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panic(err)
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}
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defer f.Close()
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syscall.Syscall(
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syscall.SYS_IOCTL,
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f.Fd(),
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MTIOCTOP,
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uintptr(unsafe.Pointer(
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&Operation{
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Op: MTSEEK,
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Count: int32(*record),
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},
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)),
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)
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}
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