OpenOfflineFile not working with os.Open

[XSAM]

I am using the OpenOfflineFile function to read libpcap data. I have tried these following functions:

• os.Open()
• *TCPConn.File()
• os.Stdin

Only os.Stdin works fine. The others will throw Read Error after normally read few packages.

Here is the sample code about os.Open()

file, err = os.Open("/tmp/tmp.pcap")
handle, err := pcap.OpenOfflineFile(file)
source := gopacket.NewPacketSource(handle, handle.LinkType())

// Fetch packet
for {
	packet, err := source.NextPacket()
	// Will throw `Read Error`
	if err != nil {
		if err == io.EOF {
			break
		}
		break
	}
}

Environment:

• macOS 10.14.6, Golang 1.14.1, libpcap 1.9.1
• Docker 19.03.5, Base image: debian: 10.3, Golang 1.14.2, libpcap 1.9.1

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PS: OpenOffline works fine. But I want to read libpcap data through TCP connection.