// WSUG Chapter IO

[[ChapterIO]]

== File Input, Output, and Printing

[[ChIOIntroductionSection]]

=== Introduction

This chapter will describe input and output of capture data.

* Open capture files in various capture file formats

* Save/Export capture files in various capture file formats

* Merge capture files together

* Import text files containing hex dumps of packets

* Print packets

[[ChIOOpenSection]]

=== Open capture files

Wireshark can read in previously saved capture files. To read them, simply
select the menu:File[Open] menu or toolbar item. Wireshark will then pop up
the “File Open” dialog box, which is discussed in more detail in <<ChIOOpen>>.

[TIP]
.You can use drag and drop to open files
====
You can open a file by simply dragging it in your file manager and dropping it
onto Wireshark’s main window. However, drag and drop may not be available in all
desktop environments.
====

If you haven’t previously saved the current capture file you will be asked to
do so to prevent data loss. This warning can be disabled in the preferences.

In addition to its native file format (pcapng), Wireshark can read and write
capture files from a large number of other packet capture programs as well. See
<<ChIOInputFormatsSection>> for the list of capture formats Wireshark
understands.

[[ChIOOpen]]

==== The “Open Capture File” dialog box

The “Open Capture File” dialog box allows you to search for a capture file
containing previously captured packets for display in Wireshark. The following
sections show some examples of the Wireshark “Open File” dialog box. The
appearance of this dialog depends on the system. However, the functionality
should be the same across systems.

Common dialog behaviour on all systems:

* Select files and directories.

* Click the btn:[Open] or btn:[OK] button to accept your selected file and
  open it.

* Click the btn:[Cancel] button to go back to Wireshark and not load a capture file.

Wireshark extensions to the standard behaviour of these dialogs:

* View file preview information such as the filesize and the number of packets
  in a selected a capture file.

* Specify a display filter with the btn:[Filter] button and filter field.
  This filter will be used when opening the new file. The text field background
  becomes green for a valid filter string and red for an invalid one. Clicking
  on the btn:[Filter] button causes Wireshark to pop up the “Filters”
  dialog box (which is discussed further in <<ChWorkDisplayFilterSection>>).
+
// XXX - we need a better description of these read filters

* Specify which type of name resolution is to be performed for all packets by
  clicking on one of the “... name resolution” check buttons. Details about name
  resolution can be found in <<ChAdvNameResolutionSection>>.

[TIP]
.Save a lot of time loading huge capture files
====
You can change the display filter and name resolution settings later while
viewing the packets. However, loading huge capture files can take a significant
amount of extra time if these settings are changed later, so in such situations
it can be a good idea to set at least the filter in advance here.
====

[[ChIOOpenFileDialogWin32]]

.“Open” on Microsoft Windows
image::wsug_graphics/ws-open-win32.png[{screenshot-attrs}]

This is the common Windows file open dialog - plus some Wireshark extensions.

Specific for this dialog:

* The btn:[Help] button will lead you to this section of this “User’s Guide”.

[[ChIOOpenFileDialog]]

.“Open” - Linux and UNIX
image::wsug_graphics/ws-open-gtk24.png[{screenshot-attrs}]

This is the common Gimp/GNOME file open dialog plus some Wireshark extensions.

Specific for this dialog:

* The btn:[+] button allows you to add a directory selected in the
  right-hand pane to the favorites list on the left. These changes are
  persistent.

* The btn:[-] button allows you to remove a selected directory from the list.
  Some items (such as “Desktop”) cannot be removed from the favorites list.

* If Wireshark doesn’t recognize the selected file as a capture file it will
  grey out the btn:[Open] button.

// XXX Add macOS


[[ChIOInputFormatsSection]]


==== Input File Formats

The following file formats from other capture tools can be opened by Wireshark:

* pcapng. A flexible, extensible successor to the libpcap format. Wireshark 1.8 and later
  save files as pcapng by default. Versions prior to 1.8 used libpcap.

* libpcap. The default format used by the _libpcap_ packet capture library. Used
  by _tcpdump, _Snort_, _Nmap_, _Ntop_, and many other tools.

* Oracle (previously Sun) _snoop_ and _atmsnoop_

* Finisar (previously Shomiti) _Surveyor_ captures

* Microsoft _Network Monitor_ captures

* Novell _LANalyzer_ captures

* AIX _iptrace_ captures

* Cinco Networks NetXray captures

* Network Associates Windows-based Sniffer and Sniffer Pro captures

* Network General/Network Associates DOS-based Sniffer (compressed or uncompressed) captures

* AG Group/WildPackets/Savvius EtherPeek/TokenPeek/AiroPeek/EtherHelp/PacketGrabber captures

* RADCOM’s WAN/LAN Analyzer captures

* Network Instruments Observer version 9 captures

* Lucent/Ascend router debug output

* HP-UX’s nettl

* Toshiba’s ISDN routers dump output

* ISDN4BSD _i4btrace_ utility

* traces from the EyeSDN USB S0

* IPLog format from the Cisco Secure Intrusion Detection System

* pppd logs (pppdump format)

* the output from VMS’s TCPIPtrace/TCPtrace/UCX$TRACE utilities

* the text output from the DBS Etherwatch VMS utility

* Visual Networks’ Visual UpTime traffic capture

* the output from CoSine L2 debug

* the output from Accellent’s 5Views LAN agents

* Endace Measurement Systems’ ERF format captures

* Linux Bluez Bluetooth stack hcidump -w traces

* Catapult DCT2000 .out files

* Gammu generated text output from Nokia DCT3 phones in Netmonitor mode

* IBM Series (OS/400) Comm traces (ASCII &amp; UNICODE)

* Juniper Netscreen snoop captures

* Symbian OS btsnoop captures

* Tamosoft CommView captures

* Textronix K12xx 32bit .rf5 format captures

* Textronix K12 text file format captures

* Apple PacketLogger captures

* Captures from Aethra Telecommunications’ PC108 software for their test instruments

New file formats are added from time to time.

It may not be possible to read some formats dependent on the packet types
captured. Ethernet captures are usually supported for most file formats but it
may not be possible to read other packet types such as PPP or IEEE 802.11 from
all file formats.

[[ChIOSaveSection]]

=== Saving captured packets

You can save captured packets simply by using the menu:File[Save As...] menu
item. You can choose which packets to save and which file format to be used.

Not all information will be saved in a capture file. For example, most file
formats don’t record the number of dropped packets. See
<<ChAppFilesCaptureFilesSection>> for details.

[[ChIOSaveAs]]

==== The “Save Capture File As” dialog box

The “Save Capture File As” dialog box allows you to save the current capture
to a file. The following sections show some examples of this dialog box. The
appearance of this dialog depends on the system. However, the functionality
should be the same across systems.

[[ChIOSaveAsFileWin32]]

.“Save” on Microsoft Windows
image::wsug_graphics/ws-save-as-win32.png[{screenshot-attrs}]

This is the common Windows file save dialog with some additional Wireshark extensions.

Specific behavior for this dialog:

* If available, the “Help” button will lead you to this section of this “User’s Guide”.

* If you don’t provide a file extension to the filename (e.g. `.pcap`) Wireshark
  will append the standard file extension for that file format.

[[ChIOSaveAsFile2]]

.“Save” on Linux and UNIX
image::wsug_graphics/ws-save-as-gtk24.png[{screenshot-attrs}]

This is the common Gimp/GNOME file save dialog with additional Wireshark extensions.

Specific for this dialog:

* Clicking on the + at “Browse for other folders” will allow you to browse files and folders in your file system.

// XXX Add macOS

With this dialog box, you can perform the following actions:

. Type in the name of the file you wish to save the captured packets in, as a
  standard file name in your file system.

. Select the directory to save the file into.

. Select the range of the packets to be saved. See <<ChIOPacketRangeSection>>.

. Specify the format of the saved capture file by clicking on the File type drop
  down box. You can choose from the types described in
  <<ChIOOutputFormatsSection>>.

Some capture formats may not be available depending on the packet types captured.

[TIP]
.Wireshark can convert file formats
====
You can convert capture files from one format to another by reading in a capture
file and writing it out using a different format.
====

. Click the btn:[Save] or btn:[OK] button to accept your selected file and
  save to it. If Wireshark has a problem saving the captured packets to the file
  you specified it will display an error dialog box. After clicking btn:[OK]
  on that error dialog box you can try again.

. Click on the btn:[Cancel] button to go back to Wireshark without saving any
  packets.

[[ChIOOutputFormatsSection]]

==== Output File Formats

Wireshark can save the packet data in its native file format (pcapng) and in the
file formats of other protocol analyzers so other tools can read the capture
data.


[WARNING]
.Different file formats have different time stamp accuracies
====
Saving from the currently used file format to a different format may reduce the
time stamp accuracy; see the <<ChAdvTimestamps>> for details.
====

The following file formats can be saved by Wireshark (with the known file extensions):

* pcapng ({asterisk}.pcapng). A flexible, extensible successor to the
  libpcap format. Wireshark 1.8 and later save files as pcapng by
  default. Versions prior to 1.8 used libpcap.

* libpcap, tcpdump and various other tools using tcpdump’s capture
  format ({asterisk}.pcap,{asterisk}.cap,{asterisk}.dmp)

* Accellent 5Views ({asterisk}.5vw)

* HP-UX’s nettl ({asterisk}.TRC0,{asterisk}.TRC1)

* Microsoft Network Monitor - NetMon ({asterisk}.cap)

* Network Associates Sniffer - DOS ({asterisk}.cap,{asterisk}.enc,{asterisk}.trc,*fdc,{asterisk}.syc)

* Network Associates Sniffer - Windows ({asterisk}.cap)

* Network Instruments Observer version 9 ({asterisk}.bfr)

* Novell LANalyzer ({asterisk}.tr1)

* Oracle (previously Sun) snoop ({asterisk}.snoop,{asterisk}.cap)

* Visual Networks Visual UpTime traffic ({asterisk}.{asterisk})

New file formats are added from time to time.

Whether or not the above tools will be more helpful than Wireshark is a different question ;-)


[NOTE]
.Third party protocol analyzers may require specific file extensions
====
Wireshark examines a file’s contents to determine its type. Some other protocol
analyzers only look at a filename extensions. For example, you might need to use
the `.cap` extension in order to open a file using _Sniffer_.
====

[[ChIOMergeSection]]

=== Merging capture files

Sometimes you need to merge several capture files into one. For example, this can
be useful if you have captured simultaneously from multiple interfaces at once
(e.g. using multiple instances of Wireshark).

There are three ways to merge capture files using Wireshark:

* Use the menu:File[Merge] menu to open the “Merge” dialog. See
  <<ChIOMergeDialog>>. This menu item will be disabled unless you have loaded a
  capture file.

* Use _drag and drop_ to drop multiple files on the main window. Wireshark will
  try to merge the packets in chronological order from the dropped files into a
  newly created temporary file. If you drop only a single file it will simply
  replace the existing capture.

* Use the `mergecap` tool, a command line tool to merge capture files.
  This tool provides the most options to merge capture files. See
  <<AppToolsmergecap>> for details.

[[ChIOMergeDialog]]

==== The “Merge with Capture File” dialog box

This dialog box let you select a file to be merged into the currently loaded
file. If your current data has not been saved you will be asked to save it
first.

Most controls of this dialog will work the same way as described in the “Open
Capture File” dialog box, see <<ChIOOpen>>.

Specific controls of this merge dialog are:

_Prepend packets to existing file_::
Prepend the packets from the selected file before the currently loaded packets.

_Merge packets chronologically_::
Merge both the packets from the selected and currently loaded file in chronological order.

_Append packets to existing file_::
Append the packets from the selected file after the currently loaded packets.


[[ChIOMergeFileTab]]

.The system specific “Merge Capture File As” dialog box

[[ChIOMergeFileWin32]]

.“Merge” on Microsoft Windows
image::wsug_graphics/ws-merge-win32.png[{screenshot-attrs}]

This is the common Windows file open dialog with additional Wireshark extensions.

[[ChIOMergeFile2]]

.“Merge” on Linux and UNIX
image::wsug_graphics/ws-merge-gtk24.png[{screenshot-attrs}]

This is the common Gimp/GNOME file open dialog with additional Wireshark extensions.


[[ChIOImportSection]]

=== Import hex dump

Wireshark can read in an ASCII hex dump and write the data described into a
temporary libpcap capture file. It can read hex dumps with multiple packets in
them, and build a capture file of multiple packets. It is also capable of
generating dummy Ethernet, IP and UDP, TCP, or SCTP headers, in order to build
fully processable packet dumps from hexdumps of application-level data only.

Wireshark understands a hexdump of the form generated by `od -Ax -tx1 -v`. In
other words, each byte is individually displayed and surrounded with a space.
Each line begins with an offset describing the position in the packet, each
new packet starts with an offset of 0 and there is a space separating the
offset from the following bytes. The offset is a hex number (can also be octal
or decimal), of more than two hex digits.
Here is a sample dump that can be imported:

----
000000 00 e0 1e a7 05 6f 00 10 ........
000008 5a a0 b9 12 08 00 46 00 ........
000010 03 68 00 00 00 00 0a 2e ........
000018 ee 33 0f 19 08 7f 0f 19 ........
000020 03 80 94 04 00 00 10 01 ........
000028 16 a2 0a 00 03 50 00 0c ........
000030 01 01 0f 19 03 80 11 01 ........
----

There is no limit on the width or number of bytes per line. Also the text dump
at the end of the line is ignored. Byte and hex numbers can be uppercase or
lowercase. Any text before the offset is ignored, including email forwarding
characters _>_. Any lines of text between the bytestring lines are ignored.
The offsets are used to track the bytes, so offsets must be correct. Any line
which has only bytes without a leading offset is ignored. An offset is
recognized as being a hex number longer than two characters. Any text after the
bytes is ignored (e.g. the character dump). Any hex numbers in this text are
also ignored. An offset of zero is indicative of starting a new packet, so a
single text file with a series of hexdumps can be converted into a packet
capture with multiple packets. Packets may be preceded by a timestamp. These are
interpreted according to the format given. If not the first packet is
timestamped with the current time the import takes place. Multiple packets are
written with timestamps differing by one microsecond each. In general, short of
these restrictions, Wireshark is pretty liberal about reading in hexdumps and
has been tested with a variety of mangled outputs (including being forwarded
through email multiple times, with limited line wrap etc.)

There are a couple of other special features to note. Any line where the first
non-whitespace character is `#` will be ignored as a comment. Any line beginning
with `#TEXT2PCAP` is a directive and options can be inserted after this command to
be processed by Wireshark. Currently there are no directives implemented. In the
future these may be used to give more fine grained control on the dump and the
way it should be processed e.g. timestamps, encapsulation type etc. Wireshark
also allows the user to read in dumps of application-level data, by inserting
dummy L2, L3 and L4 headers before each packet. The user can elect to insert
Ethernet headers, Ethernet and IP, or Ethernet, IP and UDP/TCP/SCTP headers
before each packet. This allows Wireshark or any other full-packet decoder to
handle these dumps.

[[ChIOImportDialog]]

==== The “Import from Hex Dump” dialog box

This dialog box lets you select a text file, containing a hex dump of packet
data, to be imported and set import parameters.

[[ChIOFileImportDialog]]

.The “Import from Hex Dump” dialog
image::wsug_graphics/ws-file-import.png[{screenshot-attrs}]

Specific controls of this import dialog are split in two sections:

Import from:: Determine which input file has to be imported and how it is to be
interpreted.

Encapsulation:: Determine how the data is to be encapsulated.

The import parameters are as follows:

_Filename / Browse_::
Enter the name of the text file to import. You can use _Browse_ to browse for a
file.

_Offsets_::
Select the radix of the offsets given in the text file to import. This is
usually hexadecimal, but decimal and octal are also supported. Select _None_
when only the bytes are present. These will be imported as a single packet.

_Timestamp Format_::
This is the format specifier used to parse the timestamps in the text file to
import. It uses a simple syntax to describe the format of the timestamps, using
%H for hours, %M for minutes, %S for seconds, etc. The straightforward HH:MM:SS
format is covered by %T. For a full definition of the syntax look for
`strptime(3)`. If there are no timestamps in the text file to import leave this
field empty and timestamps will be generated based on the time of import.

_Direction indication_::
Tick this box if the text file to import has direction indicators before each
frame. These are on a separate line before each frame and start with either
_I_ or _i_ for input and _O_ or _o_ for output.

The encapsulation parameters are as follows:

_Encapsulation type_::
Here you can select which type of frames you are importing. This all depends on
from what type of medium the dump to import was taken. It lists all types that
Wireshark understands, so as to pass the capture file contents to the right
dissector.

_Dummy header_::
When Ethernet encapsulation is selected you have to option to prepend dummy
headers to the frames to import. These headers can provide artificial Ethernet,
IP, UDP, TCP or SCTP headers or SCTP data chunks. When selecting a type of
dummy header the applicable entries are enabled, others are grayed out and
default values are used.
When the _Wireshark Upper PDU export_ encapsulation is selected the option
_ExportPDU_ becomes available. This allows you to enter the name of the
dissector these frames are to be directed to.

_Maximum frame length_::
You may not be interested in the full frames from the text file, just the first
part. Here you can define how much data from the start of the frame you want to
import. If you leave this open the maximum is set to 256kiB.

Once all input and import parameters are setup click btn:[Import] to start the
import. If your current data wasn’t saved before you will be asked to save it
first.

When completed there will be a new capture file loaded with the frames imported
from the text file.

[[ChIOFileSetSection]]

=== File Sets

When using the “Multiple Files” option while doing a capture (see:
<<ChCapCaptureFiles>>), the capture data is spread over several capture files,
called a file set.

As it can become tedious to work with a file set by hand, Wireshark provides
some features to handle these file sets in a convenient way.

.How does Wireshark detect the files of a file set?
****
A filename in a file set uses the format Prefix_Number_DateTimeSuffix which
might look something like `test_00001_20210714183910.pcap`. All files of a file
set share the same prefix (e.g. “test”) and suffix (e.g. “.pcap”) and a
varying middle part.

To find the files of a file set, Wireshark scans the directory where the
currently loaded file resides and checks for files matching the filename pattern
(prefix and suffix) of the currently loaded file.

This simple mechanism usually works well but has its drawbacks. If several file
sets were captured with the same prefix and suffix, Wireshark will detect them
as a single file set. If files were renamed or spread over several directories
the mechanism will fail to find all files of a set.
****

The following features in the menu:File[File Set] submenu are available to work
with file sets in a convenient way:

*  The “List Files” dialog box will list the files Wireshark has recognized as
   being part of the current file set.

*  btn:[Next File] closes the current and opens the next file in the file
   set.

*  btn:[Previous File] closes the current and opens the previous file in the
   file set.

[[ChIOFileSetListDialog]]

==== The “List Files” dialog box

.The “List Files” dialog box
image::wsug_graphics/ws-file-set-dialog.png[{screenshot-attrs}]

Each line contains information about a file of the file set:

*  _Filename_ the name of the file. If you click on the filename (or the radio
   button left to it), the current file will be closed and the corresponding
   capture file will be opened.

*  _Created_ the creation time of the file

*  _Last Modified_ the last time the file was modified

*  _Size_ the size of the file

The last line will contain info about the currently used directory where all of
the files in the file set can be found.

The content of this dialog box is updated each time a capture file is
opened/closed.

The btn:[Close] button will, well, close the dialog box.

[[ChIOExportSection]]

=== Exporting data

Wireshark provides several ways and formats to export packet data. This section
describes general ways to export data from the main Wireshark application. There
are more specialized functions to export specific data which are described
elsewhere.

// XXX - add detailed descriptions of the output formats and some sample output, too.

// XXX Most of this content is no longer relevant in the current GTK+ UI, much less Qt.

[[ChIOExportPlainDialog]]

==== The “Export as Plain Text File” dialog box

[[ChIOExportPlain]]

Export packet data into a plain ASCII text file, much like the format used to print packets.

[TIP]
====
If you would like to be able to import any previously exported packets from a
plain text file it is recommended that you:

*  Add the “Absolute date and time” column.

*  Temporarily hide all other columns.

*  Disable the menu:Edit[Preferences,Protocols,Data] “Show not dissected data
   on new Packet Bytes pane” preference. More details are provided in
   <<ChCustPreferencesSection>>

*  Include the packet summary line.

*  Exclude column headings.

*  Exclude packet details.

*  Include the packet bytes.
====

.The “Export as Plain Text File” dialog box
image::wsug_graphics/ws-export-plain.png[{screenshot-attrs}]

*  The “Export to file:” frame chooses the file to export the packet data to.

*  The “Packet Range” frame is described in <<ChIOPacketRangeSection>>.

*  The “Packet Details” frame is described in <<ChIOPacketFormatSection>>.

[[ChIOExportPSDialog]]

==== The “Export as PostScript File” dialog box

.The “Export as PostScript File” dialog box
image::wsug_graphics/ws-export-ps.png[{screenshot-attrs}]

*  _Export to file:_ frame chooses the file to export the packet data to.

*  The _Packet Range_ frame is described in <<ChIOPacketRangeSection>>.

*  The _Packet Details_ frame is described in <<ChIOPacketFormatSection>>.

[[ChIOExportCSVDialog]]

==== The “Export as CSV (Comma Separated Values) File” dialog box

// XXX - add screenshot

Export packet summary into CSV, used e.g. by spreadsheet programs to im-/export data.

//<!--<figure>
//      <title>The “Export as Comma Separated Values File” dialog box</title>
//      <graphic entityref="WiresharkExportCSVDialog" format="PNG"/>
//    </figure>-->

*  _Export to file:_ frame chooses the file to export the packet data to.

*  The _Packet Range_ frame is described in <<ChIOPacketRangeSection>>.

[[ChIOExportCArraysDialog]]

==== The “Export as C Arrays (packet bytes) file” dialog box

// XXX - add screenshot

Export packet bytes into C arrays so you can import the stream data into your own C program.

//        <figure>
//        <title>The “Export as C Arrays (packet bytes) file” dialog box</title>
//        <graphic entityref="WiresharkExportCArraysDialog" format="PNG"/>
//        </figure>

*  _Export to file:_ frame chooses the file to export the packet data to.

*  The _Packet Range_ frame is described in <<ChIOPacketRangeSection>>.

[[ChIOExportPSMLDialog]]

==== The “Export as PSML File” dialog box

Export packet data into PSML. This is an XML based format including only the
packet summary. The PSML file specification is available at:
https://web.archive.org/web/20141115200425/http://www.nbee.org/doku.php?id=netpdl:psml_specification[].

.The “Export as PSML File” dialog box
image::wsug_graphics/ws-export-psml.png[{screenshot-attrs}]

*  _Export to file:_ frame chooses the file to export the packet data to.

*  The _Packet Range_ frame is described in <<ChIOPacketRangeSection>>.

There’s no such thing as a packet details frame for PSML export, as the packet
format is defined by the PSML specification.

[[ChIOExportPDMLDialog]]

==== The “Export as PDML File” dialog box

Export packet data into PDML. This is an XML based format including the packet
details. The PDML file specification is available at:
https://web.archive.org/web/20140416072301/http://www.nbee.org/doku.php?id=netpdl:pdml_specification[].

[NOTE]
====
The PDML specification is not officially released and Wireshark’s implementation
of it is still in an early beta state, so please expect changes in future
Wireshark versions.
====

.The “Export as PDML File” dialog box
image::wsug_graphics/ws-export-pdml.png[{screenshot-attrs}]

*  _Export to file:_ frame chooses the file to export the packet data to.

*  The _Packet Range_ frame is described in <<ChIOPacketRangeSection>>.

There’s no such thing as a packet details frame for PDML export, as the packet
format is defined by the PDML specification.

[[ChIOExportSelectedDialog]]

==== The “Export selected packet bytes” dialog box

Export the bytes selected in the “Packet Bytes” pane into a raw binary file.

.The “Export Selected Packet Bytes” dialog box
image::wsug_graphics/ws-export-selected.png[{screenshot-attrs}]

*  _Name:_ the filename to export the packet data to.

*  The _Save in folder:_ field lets you select the folder to save to (from some predefined folders).

*  _Browse for other folders_ provides a flexible way to choose a folder.

[[ChIOExportObjectsDialog]]

==== The “Export Objects” dialog box

This feature scans through the selected protocol's streams in the currently
open capture file or running capture and allows the user to export reassembled
objects to the disk. For example, if you select HTTP, you can export HTML
documents, images, executables, and any other files transferred over HTTP
to the disk. If you have a capture running, this list is automatically
updated every few seconds with any new objects seen. The saved objects can then
be opened or examined independently of Wireshark.

.The “Export Objects” dialog box
image::wsug_graphics/ws-export-objects.png[{screenshot-attrs}]

Columns:

*  _Packet:_ The packet number in which this object was found. In some
   cases, there can be multiple objects in the same packet.

*  _Hostname:_ The hostname of the server that sent this object.

*  _Content Type:_ The content type of this object.

*  _Size:_ The size of this object in bytes.

*  _Filename:_ The filename for this object. Each protocol generates
   the filename differently. For example, HTTP uses the
   final part of the URI and IMF uses the subject of the email.

Inputs:

*  _Text Filter:_ Only displays objects containing the specified text string.

*  _Help:_ Opens the “Export Objects” section in the user’s guide.

*  _Save All:_ Saves all objects (including those not displayed) using the filename from the
   filename column. You will be asked what directory / folder to save them in.

*  _Close:_ Closes the “Export Objects” dialog.

*  _Save:_ Saves the currently selected object as a filename you specify. The
   default filename to save as is taken from the filename column of the objects
   list.

[[ChIOPrintSection]]

=== Printing packets

To print packets, select the menu:File[Print...] menu item. When you
do this Wireshark pops up the “Print” dialog box as shown in
<<ChIOPrintDialogBox>>.

==== The “Print” dialog box

[[ChIOPrintDialogBox]]

.The “Print” dialog box
image::wsug_graphics/ws-print.png[{screenshot-attrs}]

The following fields are available in the Print dialog box: _Printer_::
This field contains a pair of mutually exclusive radio buttons:

* _Plain Text_ specifies that the packet print should be in plain text.

* _PostScript_ specifies that the packet print process should use PostScript to
  generate a better print output on PostScript aware printers.

* _Output to file:_ specifies that printing be done to a file, using the
  filename entered in the field or selected with the browse button.
+
This field is where you enter the _file_ to print to if you have selected Print
to a file, or you can click the button to browse the filesystem. It is greyed
out if Print to a file is not selected.

* _Print command_ specifies that a command be used for printing.
+
[NOTE]
.Note!
====
These _Print command_ fields are not available on windows platforms.
====
+
This field specifies the command to use for printing. It is typically `lpr`. You
would change it to specify a particular queue if you need to print to a queue
other than the default. An example might be:
+
----
$ lpr -Pmypostscript
----
+
This field is greyed out if _Output to file:_ is checked above.

_Packet Range_::
Select the packets to be printed, see <<ChIOPacketRangeSection>>

_Packet Format_::
Select the output format of the packets to be printed. You can choose, how each
packet is printed, see <<ChIOPacketFormatFrame>>

[[ChIOPacketRangeSection]]

=== The “Packet Range” frame

The packet range frame is a part of various output related dialog boxes. It
provides options to select which packets should be processed by the output
function.

[[ChIOPacketRangeFrame]]

.The “Packet Range” frame
image::wsug_graphics/ws-packet-range.png[{screenshot-attrs}]

If the btn:[Captured] button is set (default), all packets from the selected rule
will be processed. If the btn:[Displayed] button is set, only the currently
displayed packets are taken into account to the selected rule.

* _All packets_ will process all packets.

* _Selected packet only_ process only the selected packet.

* _Marked packets only_ process only the marked packets.

* _From first to last marked packet_ process the packets from the first to the
  last marked one.

* _Specify a packet range_ process a user specified range of packets, e.g.
  specifying _5,10-15,20-_ will process the packet number five, the packets from
  packet number ten to fifteen (inclusive) and every packet from number twenty
  to the end of the capture.

[[ChIOPacketFormatSection]]

=== The Packet Format frame

The packet format frame is a part of various output related dialog boxes. It
provides options to select which parts of a packet should be used for the output
function.

[[ChIOPacketFormatFrame]]

.The “Packet Format” frame
image::wsug_graphics/ws-packet-format.png[{screenshot-attrs}]

* _Packet summary line_ enable the output of the summary line, just as in the
  “Packet List” pane.

* _Packet details_ enable the output of the packet details tree.

* _All collapsed_ the info from the “Packet Details” pane in “all collapsed”
  state.

* _As displayed_ the info from the “Packet Details” pane in the current state.

* _All expanded_ the info from the “Packet Details” pane in “all expanded”
  state.

* _Packet bytes_ enable the output of the packet bytes, just as in the “Packet
  Bytes” pane.

* _Each packet on a new page_ put each packet on a separate page (e.g. when
  saving/printing to a text file, this will put a form feed character between
  the packets).

// End of WSUG Chapter IO
