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Write interface description block to PCAPNG file

Since R2020b



    interfaceID = writeInterfaceDescriptionBlock(pcapngObj,linkType,interface) writes an interface description block to the PCAPNG file specified in the PCAPNG file writer object, pcapngObj. Input linkType specifies the unique identifier for the protocol and input interface specifies the interface on which the protocol packets are captured. This object function returns the unique identifier for the interface.


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    Create a default PCAPNG file writer object.

    pcapngObj = pcapngWriter;

    Write the interface block for 5G New Radio (NR). 5G NR packets do not have a valid link type. As per Tcpdump, if a valid link type is not present, specify the link type of SLL packet.

    interface = '5GNR';       % Interface name
    linkType = 113;           % Link type of SLL packet
    interfaceID = writeInterfaceDescriptionBlock(pcapngObj,linkType,interface);

    Input Arguments

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    The pcapngWriter object does not overwrite the existing PCAPNG file. Each time when you create this object, specify a unique PCAPNG file name.

    PCAPNG file writer object, specified as a pcapngWriter object.

    Unique identifier for a protocol, specified as an integer in the range [0, 65,535].

    Data Types: double

    Name of the interface on which protocol packets are captured, specified as a character vector or a string scalar in 8-bit unicode transformation format (UTF-8) format.

    Data Types: char | string

    Output Arguments

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    Unique identifier for an interface, specified as a nonnegative scalar.

    Data Types: double


    [1] Tuexen, M. “PCAP Next Generation (Pcapng) Capture File Format.” 2020.

    [2] Group, The Tcpdump. “Tcpdump/Libpcap Public Repository.” Accessed May 20, 2020.

    [3] “Development/LibpcapFileFormat - The Wireshark Wiki.” Accessed May 20, 2020.

    Extended Capabilities

    C/C++ Code Generation
    Generate C and C++ code using MATLAB® Coder™.

    Version History

    Introduced in R2020b

    See Also