ns-3

https://www.nsnam.org/docs/release/3.26/manual/singlehtml/
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ns-3 is a discrete-event network simulator implemented in C++ and Python, primarily used to simulate...
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### Run a single C++ example with --example=udp-echo

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Use this command to run a single C++ example. The relative path for the example does not need to be included, and the example must be registered in the relevant examples-to-run.py file.

```bash
$ ./test.py --example=udp-echo

```

```text
PASS: Example examples/udp/udp-echo

```

--------------------------------

### Emitter setup with Names::Add and Simulator::Schedule

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Creates an Emitter object, adds it to the Names system, and schedules its Start method. The Emitter is not associated with an ns-3 node, so it must be started manually.

```cpp
Ptr<Emitter> emitter = CreateObject<Emitter> ();
Names::Add ("/Names/Emitter", emitter);

// The Emitter object is not associated with an ns-3 node, so
// it won't get started automatically, so we need to do this ourselves
Simulator::Schedule (Seconds (0.0), &Emitter::Start, emitter);

```

--------------------------------

### Declare multi-file C++ example

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Shows how to split an example implementation among several source files. Include the additional files as explicit sources of the example.

```python
obj = bld.create_ns3_program('new-module-example', [new-module])
obj.source = ['new-module-example.cc', 'new-module-example-part.cc']
```

--------------------------------

### Run a single Python example with --pyexample

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Use this command to run a single Python example. The relative path for the example must be included, and Python examples need their extensions.

```bash
$ ./test.py --pyexample=examples/tutorial/first.py

```

```text
PASS: Example examples/tutorial/first.py

```

--------------------------------

### Build with build.py enabling examples and tests

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Run build.py with --enable-examples and --enable-tests to build with examples and tests.

```bash
$ ./build.py --enable-examples --enable-tests
```

```text
170 of 170 tests passed (170 passed, 0 skipped, 0 failed, 0 crashed, 0 valgrind errors)
```

--------------------------------

### Build with waf enabling examples and tests

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Run waf configure with --enable-examples and --enable-tests, then build to enable examples and tests.

```bash
$ ./waf configure --enable-examples --enable-tests
$ ./waf build
```

```text
170 of 170 tests passed (170 passed, 0 skipped, 0 failed, 0 crashed, 0 valgrind errors)
```

--------------------------------

### Build with build.py without examples or tests

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Run build.py from the ns-3-allinone directory to build without examples or tests.

```bash
$ ./build.py
```

```text
0 of 0 tests passed (0 passed, 0 skipped, 0 failed, 0 crashed, 0 valgrind errors)
```

--------------------------------

### ConfigureFile() usage example from seventh.cc

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Example call to ConfigureFile() as used in the seventh.cc code, configuring a formatted output file.

```cpp
fileHelper.ConfigureFile ("seventh-packet-byte-count",
                          FileAggregator::FORMATTED);
```

--------------------------------

### Run realtime-udp-echo example

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Command to run the real-time UDP echo example script, which demonstrates how to configure real-time behavior.

```bash
$ ./waf --run realtime-udp-echo

```

--------------------------------

### Run test.py with examples and tests

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Output of running test.py when examples and tests are enabled, showing that all tests pass.

```text
170 of 170 tests passed (170 passed, 0 skipped, 0 failed, 0 crashed, 0 valgrind errors)
```

--------------------------------

### Configure ns-3 with tests and examples enabled

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Run this command during the configuration stage to enable tests and examples so that test.py can run them. This is required before building and running tests.

```bash
$ ./waf --configure --enable-examples --enable-tests

```

--------------------------------

### File helper example output file (first 10 lines)

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

First 10 lines of the output file 'file-helper-example.txt' created by the file-helper-example.cc example. Shows the formatted output with time and count columns.

```text
Time (Seconds) = 0.203  Count = 1
Time (Seconds) = 0.702  Count = 2
Time (Seconds) = 1.404  Count = 3
Time (Seconds) = 2.368  Count = 4
Time (Seconds) = 3.364  Count = 5
Time (Seconds) = 3.579  Count = 6
Time (Seconds) = 5.873  Count = 7
Time (Seconds) = 6.410  Count = 8
Time (Seconds) = 6.472  Count = 9
...

```

--------------------------------

### Declare Python example in examples/wscript

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Specify a Python example using the 'register_ns3_script' function. The second argument is the list of modules the Python example depends on.

```python
bld.register_ns3_script('new-module-example.py', ['new-module'])
```

--------------------------------

### Configure .ns3rc to enable examples and tests

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Modified .ns3rc file with examples_enabled and tests_enabled set to True, enabling examples and tests to be built and run.

```python
#! /usr/bin/env python

# A list of the modules that will be enabled when ns-3 is run.
# Modules that depend on the listed modules will be enabled also.
#
# All modules can be enabled by choosing 'all_modules'.
modules_enabled = ['all_modules']

# Set this equal to true if you want examples to be run.
examples_enabled = True

# Set this equal to true if you want tests to be run.
tests_enabled = True
```

--------------------------------

### Build with waf without examples or tests

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Run waf configure and build from the top level ns-3 directory to build without examples or tests.

```bash
$ ./waf configure
$ ./waf build
```

```text
0 of 0 tests passed (0 passed, 0 skipped, 0 failed, 0 crashed, 0 valgrind errors)
```

--------------------------------

### Formatted output file example

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Example output file created by the FileAggregator example, showing formatted values with 'Time = ... Value = ...'.

```text
Time = -5.000e+00     Value = 25
Time = -4.000e+00     Value = 16
Time = -3.000e+00     Value = 9
Time = -2.000e+00     Value = 4
Time = -1.000e+00     Value = 1
Time = 0.000e+00      Value = 0
Time = 1.000e+00      Value = 1
Time = 2.000e+00      Value = 4
Time = 3.000e+00      Value = 9
Time = 4.000e+00      Value = 16
Time = 5.000e+00      Value = 25

```

--------------------------------

### Reconfigure and build after installing GTK libraries

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

After installing a suitable GTK version, rerun waf configure and waf to enable GtkConfigStore.

```bash
$ ./waf configure --enable-examples --enable-tests
$ ./waf

```

--------------------------------

### C++ and Python example lists in src/spectrum/test/examples-to-run.py

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Defines the cpp_examples and python_examples lists that control which spectrum model examples are run by test.py. Each C++ tuple contains the example name, do_run, and do_valgrind_run flags; each Python tuple contains the example name and do_run flag.

```python
# A list of C++ examples to run in order to ensure that they remain
# buildable and runnable over time.  Each tuple in the list contains
#
#     (example_name, do_run, do_valgrind_run).
#
# See test.py for more information.
cpp_examples = [
    ("adhoc-aloha-ideal-phy", "True", "True"),
    ("adhoc-aloha-ideal-phy-with-microwave-oven", "True", "True"),
    ("adhoc-aloha-ideal-phy-matrix-propagation-loss-model", "True", "True"),
]

# A list of Python examples to run in order to ensure that they remain
# runnable over time.  Each tuple in the list contains
#
#     (example_name, do_run).
#
# See test.py for more information.
python_examples = [
    (
```

--------------------------------

### Specify build path with --buildpath

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Use this command to specify the directory where ns-3 was built when running an example. The --buildpath option is used in conjunction with --example.

```bash
$ ./test.py --buildpath=/home/craigdo/repos/ns-3-allinone-test/ns-3-dev/build/debug --example=wifi-simple-adhoc

```

--------------------------------

### Install GTK libraries for ConfigStore GUI

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Ubuntu command to install libgtk and libgtk-dev, required to use the GTK-based ConfigStore front end.

```bash
$ sudo apt-get install libgtk2.0-0 libgtk2.0-dev

```

--------------------------------

### Comma-separated output file example

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Example output file created by the FileAggregator example, showing 2 columns of values separated by commas.

```text
-5,25
-4,16
-3,9
-2,4
-1,1
0,0
1,1
2,4
3,9
4,16
5,25

```

--------------------------------

### Build ns-3 without examples or tests

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Commands to configure and build ns-3 from the top-level directory when examples and tests are disabled.

```bash
$ ./waf configure
$ ./waf build
```

--------------------------------

### Declare C++ example in examples/wscript

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Define a C++ example program in the examples/wscript file. The 'create_ns3_program' function creates a program with the given name and module dependencies. The second argument is the list of modules the program depends on; include 'new-module' in the list. Only list direct module dependencies.

```python
def build(bld):
  obj = bld.create_ns3_program('adhoc-aloha-ideal-phy',
                               ['spectrum', 'mobility'])
  obj.source = 'adhoc-aloha-ideal-phy.cc'
```

--------------------------------

### WriteProbe() usage from seventh.cc

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Example call to WriteProbe() from the seventh.cc example. It creates an Ipv4PacketProbe and writes the OutputBytes trace source for all nodes' Ipv4L3Protocol Tx trace.

```cpp
fileHelper.WriteProbe ("ns3::Ipv4PacketProbe",
                       "/NodeList/*/$ns3::Ipv4L3Protocol/Tx",
                       "OutputBytes");

```

--------------------------------

### CreateObject example

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Creates a Node instance using the CreateObject function, which initializes attributes.

```cpp
Ptr<Node> n = CreateObject<Node> ();
```

--------------------------------

### Include public header example

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Shows how users include public headers of the module in their code. The header must be declared in the wscript as shown in the previous example.

```cpp
#include "ns3/spectrum-model.h"
```

--------------------------------

### GnuplotHelper usage example from seventh.cc

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Fully worked example showing how to create a GnuplotHelper, configure the plot, and plot a probe with a key placement option. The probeType and tracePath are defined separately for IPv4.

```cpp
// Create the gnuplot helper.
GnuplotHelper plotHelper;

// Configure the plot.
// Configure the plot.  The first argument is the file name prefix
// for the output files generated.  The second, third, and fourth
// arguments are, respectively, the plot title, x-axis, and y-axis labels
plotHelper.ConfigurePlot ("seventh-packet-byte-count",
                          "Packet Byte Count vs. Time",
                          "Time (Seconds)",
                          "Packet Byte Count",
                          "png");

// Specify the probe type, trace source path (in configuration namespace), and
// probe output trace source ("OutputBytes") to plot.  The fourth argument
// specifies the name of the data series label on the plot.  The last
// argument formats the plot by specifying where the key should be placed.
plotHelper.PlotProbe (probeType,
                      tracePath,
                      "OutputBytes",
                      "Packet Byte Count",
                      GnuplotAggregator::KEY_BELOW);

```

```cpp
probeType = "ns3::Ipv4PacketProbe";
tracePath = "/NodeList/*/$ns3::Ipv4L3Protocol/Tx";

```

--------------------------------

### Usage example of SpecificFunctor

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Shows a complete example: a class A with a method Hello, and main() that creates an instance and calls the method via a SpecificFunctor. Note: this is illustrative, not real ns-3 code.

```cpp
class A
{
public:
A (int a0) : a (a0) {}
int Hello (int b0)
{
  std::cout << "Hello from A, a = " << a << " b0 = " << b0 << std::endl;
}
int a;
};

int main()
{
  A a(10);
  SpecificFunctor<A, int> sf(&a, &A::Hello);
  sf(5);
}

```

--------------------------------

### Run gnuplot-example with waf shell

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Commands to run the gnuplot-example program from the ns-3 build directory. The example is located at src/stats/examples/gnuplot-example.cc.

```bash
$ ./waf shell
$ cd build/debug/src/stats/examples
$ ./gnuplot-example
```

--------------------------------

### NS_LOG with severity prefix example

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Enables logging for all components and all severity classes, with the severity class prefixed. Shows the command and its output.

```bash
$ NS_LOG="*=all|prefix_level" ./waf --run scratch-simulator
Scratch Simulator
[ERROR] error message
[WARN] warn message
[DEBUG] debug message
[INFO] info message
[FUNCT] function message
[LOGIC] logic message
```

--------------------------------

### Direct standard output printing in C++

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Shows the most straightforward way to get information out of a program by printing to standard output with std::cout. Useful in small environments, but becomes harder to parse and control as simulations grow. The ellipsis lines are part of the original example.

```cpp
#include <iostream>
...
int main ()
{
  ...
  std::cout << "The value of x is " << x << std::endl;
  ...
}

```

--------------------------------

### test.py --help command output

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Shows the usage and options for the test.py script. Run `test.py --help` to see this command summary. Options include -b/--buildpath to specify the ns-3 build directory, -c/--constrain to filter tests by kind, -e/--example to run a single example, -d/--duration to print test durations, -u/--update-data to regenerate reference data files, and -f/--fullness to choose the duration of tests to run (QUICK, EXTENSIVE, or TAKES_FOREVER).

```text
Usage: test.py [options]

Options:
  -h, --help            show this help message and exit
  -b BUILDPATH, --buildpath=BUILDPATH
                        specify the path where ns-3 was built (defaults to the
                        build directory for the current variant)
  -c KIND, --constrain=KIND
                        constrain the test-runner by kind of test
  -e EXAMPLE, --example=EXAMPLE
                        specify a single example to run (no relative path is
                        needed)
  -d, --duration        print the duration of each test suite and example
  -e EXAMPLE, --example=EXAMPLE
                        specify a single example to run (no relative path is
                        needed)
  -u, --update-data     If examples use reference data files, get them to re-
                        generate them
  -f FULLNESS, --fullness=FULLNESS
                        choose the duration of tests to run: QUICK, EXTENSIVE,
                        or TAKES_FOREVER, where EXTENSIVE includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK and TAKES_FOREVER includes QUICK and
                        TAKES_FOREVER includes QUICK
```

--------------------------------

### Read and write ConfigStore attributes with input-defaults.xml and output-attributes.xml

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Complete example that loads defaults from input-defaults.xml, allows command-line overrides, and saves resulting attributes to output-attributes.xml before Simulator::Run(). The ConfigStore attributes Filename, Mode, and FileFormat must be set either via command-line or program statements.

```cpp
#include "ns3/config-store-module.h"
...
int main (...)
{

  Config::SetDefault ("ns3::ConfigStore::Filename", StringValue ("input-defaults.xml"));
  Config::SetDefault ("ns3::ConfigStore::Mode", StringValue ("Load"));
  Config::SetDefault ("ns3::ConfigStore::FileFormat", StringValue ("Xml"));
  ConfigStore inputConfig;
  inputConfig.ConfigureDefaults ();

  //
  // Allow the user to override any of the defaults and the above Bind () at
  // run-time, viacommand-line arguments
  //
  CommandLine cmd;
  cmd.Parse (argc, argv);

  // setup topology
  ...

  // Invoke just before entering Simulator::Run ()
  Config::SetDefault ("ns3::ConfigStore::Filename", StringValue ("output-attributes.xml"));
  Config::SetDefault ("ns3::ConfigStore::Mode", StringValue ("Save"));
  ConfigStore outputConfig;
  outputConfig.ConfigureAttributes ();
  Simulator::Run ();
}

```

--------------------------------

### Run test.py with no examples or tests

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Output of running test.py when examples and tests are disabled, showing that no tests are run.

```text
0 of 0 tests passed (0 passed, 0 skipped, 0 failed, 0 crashed, 0 valgrind errors)
```

--------------------------------

### Enable all logging with NS_LOG environment variable

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Runs the 'first' tutorial program with all logging output enabled by setting NS_LOG to the wildcard '*'.

```bash
$ NS_LOG="*" ./waf --run first

```

--------------------------------

### Run test-runner with --help

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Use this command to display the available options for the test-runner executable. It is run via waf and shows the usage and all command-line flags.

```bash
$ ./waf --run "test-runner --help"

```

--------------------------------

### Create nodes and network stacks with ns3::NodeContainer, WiFiHelper, and InternetStackHelper

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Creates two wireless nodes, configures the WiFi PHY and MAC layers for ad hoc mode, installs the internet stack, and assigns IP addresses to the nodes.

```cpp
NodeContainer nodes;
nodes.Create(2);

WifiHelper wifi;
wifi.SetMac("ns3::AdhocWifiMac");
wifi.SetPhy("ns3::WifiPhy");
NetDeviceContainer nodeDevices = wifi.Install(nodes);

InternetStackHelper internet;
internet.Install(nodes);
Ipv4AddressHelper ipAddrs;
ipAddrs.SetBase("192.168.0.0", "255.255.255.0");
ipAddrs.Assign(nodeDevices);

```

--------------------------------

### Modified .ns3rc to enable core module with examples and tests

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Modify the .ns3rc file to enable only the core module and enable examples and tests.

```python
#! /usr/bin/env python

# A list of the modules that will be enabled when ns-3 is run.
# Modules that depend on the listed modules will be enabled also.
#
# All modules can be enabled by choosing 'all_modules'.
modules_enabled = ['core']

# Set this equal to true if you want examples to be run.
examples_enabled = True

# Set this equal to true if you want tests to be run.
tests_enabled = True
```

--------------------------------

### Enable logging for a specific component with NS_LOG

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Runs the 'first' tutorial program with logging enabled only for the Ipv4L3Protocol component.

```bash
$ NS_LOG="Ipv4L3Protocol" ./waf --run first

```

--------------------------------

### Run an ns-3 simulation from Python (examples/tutorial/first.py)

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Python script that uses ns-3 Python bindings to create a point-to-point network with two nodes and run a UDP echo application. It enables logging for UDP echo client and server, sets up the network, installs the internet stack, assigns IP addresses, and schedules start/stop times for the applications. The simulation runs for 10 seconds and then destroys the simulator.

```python
import ns.applications
import ns.core
import ns.internet
import ns.network
import ns.point_to_point

ns.core.LogComponentEnable("UdpEchoClientApplication", ns.core.LOG_LEVEL_INFO)
ns.core.LogComponentEnable("UdpEchoServerApplication", ns.core.LOG_LEVEL_INFO)

nodes = ns.network.NodeContainer()
nodes.Create(2)

pointToPoint = ns.point_to_point.PointToPointHelper()
pointToPoint.SetDeviceAttribute("DataRate", ns.core.StringValue("5Mbps"))
pointToPoint.SetChannelAttribute("Delay", ns.core.StringValue("2ms"))

devices = pointToPoint.Install(nodes)

stack = ns.internet.InternetStackHelper()
stack.Install(nodes)

address = ns.internet.Ipv4AddressHelper()
address.SetBase(ns.network.Ipv4Address("10.1.1.0"), ns.network.Ipv4Mask("255.255.255.0"))

interfaces = address.Assign (devices);

echoServer = ns.applications.UdpEchoServerHelper(9)

serverApps = echoServer.Install(nodes.Get(1))
serverApps.Start(ns.core.Seconds(1.0))
serverApps.Stop(ns.core.Seconds(10.0))

echoClient = ns.applications.UdpEchoClientHelper(interfaces.GetAddress(1), 9)
echoClient.SetAttribute("MaxPackets", ns.core.UintegerValue(1))
echoClient.SetAttribute("Interval", ns.core.TimeValue(ns.core.Seconds (1.0)))
echoClient.SetAttribute("PacketSize", ns.core.UintegerValue(1024))

clientApps = echoClient.Install(nodes.Get(0))
clientApps.Start(ns.core.Seconds(2.0))
clientApps.Stop(ns.core.Seconds(10.0))

ns.core.Simulator.Run()
ns.core.Simulator.Destroy()

```

--------------------------------

### Set up bindings toolchain with bake build system

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Commands to configure, download, and build the ns-allinone-3.26 target using the bake build system, which provides an automated setup for the Python bindings toolchain. This toolchain is only supported for gcc version 4; gcc-5, gcc-6, and clang are not supported.

```bash
./bake.py configure -e ns-allinone-3.26
./bake.py download
./bake.py build

```

--------------------------------

### Build all Sphinx documentation with ./waf sphinx

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Command to build all Sphinx documentation. Run from the ns-3 root directory.

```bash
$ ./waf sphinx

```

--------------------------------

### IPv4 packet plot example network topology diagram

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

ASCII diagram showing the network topology for the IPv4 packet plot example, with two nodes connected by a point-to-point link.

```text
      node 0                 node 1
+----------------+    +----------------+
|    ns-3 TCP    |    |    ns-3 TCP    |
+----------------+    +----------------+
|    10.1.1.1    |    |    10.1.1.2    |
+----------------+    +----------------+
| point-to-point |    | point-to-point |
+----------------+    +----------------+
        |                     |
        +---------------------+
```

--------------------------------

### Example trace helper method calls

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Shows typical calls to enable pcap and ascii tracing on point-to-point and CSMA devices, including file naming conventions.

```cpp
pointToPoint.EnablePcapAll ("second");
pointToPoint.EnablePcap ("second", p2pNodes.Get (0)->GetId (), 0);
csma.EnablePcap ("third", csmaDevices.Get (0), true);
pointToPoint.EnableAsciiAll (ascii.CreateFileStream ("myfirst.tr"));

```

--------------------------------

### Enable logging via LogComponentEnable in main()

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Shows how to enable logging for UdpEchoClientApplication and UdpEchoServerApplication at LOG_LEVEL_INFO using explicit program statements.

```cpp
int
main (int argc, char *argv[])
{
  LogComponentEnable ("UdpEchoClientApplication", LOG_LEVEL_INFO);
  LogComponentEnable ("UdpEchoServerApplication", LOG_LEVEL_INFO);
  ...

```

--------------------------------

### Install traffic generator and sink applications

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Installs custom Sender and Receiver applications on nodes 0 and 1. The commented-out Config::Set line changes the destination from broadcast to a specific IP address.

```cpp
Ptr<Node> appSource = NodeList::GetNode(0);
Ptr<Sender> sender = CreateObject<Sender>();
appSource->AddApplication(sender);
sender->Start(Seconds(1));

Ptr<Node> appSink = NodeList::GetNode(1);
Ptr<Receiver> receiver = CreateObject<Receiver>();
appSink->AddApplication(receiver);
receiver->Start(Seconds(0));

//  Config::Set("/NodeList/*/ApplicationList/*/$Sender/Destination",
//              Ipv4AddressValue("192.168.0.2"));

```

--------------------------------

### List new-module directory contents

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

After creating the module, cd into new-module and list its contents to see the generated directories and wscript file.

```bash
$ cd new-module
$ ls
doc examples  helper  model  test  wscript

```

--------------------------------

### Create DoubleProbe with attributes using CreateObjectWithAttributes

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Creates a DoubleProbe with custom attributes: Name, Enabled, Start, and Stop. Start and Stop define the active interval; Stop of 0 seconds disables the stop time.

```cpp
Ptr<DoubleProbe> myprobe = CreateObjectWithAttributes<DoubleProbe> (
    "Name", StringValue ("myprobe"),
    "Enabled", BooleanValue (false),
    "Start", TimeValue (Seconds (100.0)),
    "Stop", TimeValue (Seconds (1000.0)));

```

--------------------------------

### Raw text output of configuration store

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Example content of the output-attributes.txt file after running the configuration save. It lists default attribute values, global values, and the value of the ConfigExample instance.

```text
default ns3::RealtimeSimulatorImpl::SynchronizationMode "BestEffort"
default ns3::RealtimeSimulatorImpl::HardLimit "+100000000.0ns"
default ns3::PcapFileWrapper::CaptureSize "65535"
default ns3::PacketSocket::RcvBufSize "131072"
default ns3::ErrorModel::IsEnabled "true"
default ns3::RateErrorModel::ErrorUnit "EU_BYTE"
default ns3::RateErrorModel::ErrorRate "0"
default ns3::RateErrorModel::RanVar "Uniform:0:1"
default ns3::DropTailQueue::Mode "Packets"
default ns3::DropTailQueue::MaxPackets "100"
default ns3::DropTailQueue::MaxBytes "6553500"
default ns3::Application::StartTime "+0.0ns"
default ns3::Application::StopTime "+0.0ns"
default ns3::ConfigStore::Mode "Save"
default ns3::ConfigStore::Filename "output-attributes.txt"
default ns3::ConfigStore::FileFormat "RawText"
default ns3::ConfigExample::TestInt16 "-5"
global RngSeed "1"
global RngRun "1"
global SimulatorImplementationType "ns3::DefaultSimulatorImpl"
global SchedulerType "ns3::MapScheduler"
global ChecksumEnabled "false"
value /$ns3::ConfigExample/TestInt16 "-3"

```

--------------------------------

### Check GtkConfigStore configuration with waf configure

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Run waf configure with --enable-examples --enable-tests to check whether GtkConfigStore is enabled. The output shows 'not enabled' when the required library 'gtk+-2.0 >= 2.12' is not found.

```bash
$ ./waf configure --enable-examples --enable-tests

---- Summary of optional NS-3 features:
Python Bindings               : enabled
Python API Scanning Support   : enabled
NS-3 Click Integration        : enabled
GtkConfigStore                : not enabled (library 'gtk+-2.0 >= 2.12' not found)

```

--------------------------------

### GnuplotHelper ConfigurePlot usage example in seventh.cc

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Configures a plot with the GnuplotHelper in the seventh.cc example. Creates a space separated gnuplot data file named outputFileNameWithoutExtension + ".dat", a gnuplot control file named outputFileNameWithoutExtension + ".plt", and a shell script to generate the gnuplot named outputFileNameWithoutExtension + ".sh".

```cpp
plotHelper.ConfigurePlot ("seventh-packet-byte-count",
                          "Packet Byte Count vs. Time",
                          "Time (Seconds)",
                          "Packet Byte Count");
```

--------------------------------

### Default .ns3rc configuration file

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

The default .ns3rc file enables all modules and disables examples and tests.

```python
# A list of the modules that will be enabled when ns-3 is run.
# Modules that depend on the listed modules will be enabled also.
#
# All modules can be enabled by choosing 'all_modules'.
modules_enabled = ['all_modules']

# Set this equal to true if you want examples to be run.
examples_enabled = False

# Set this equal to true if you want tests to be run.
tests_enabled = False
```

--------------------------------

### Configure and use FileHelper to write probe output

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Configures the FileHelper to write formatted output to 'file-helper-example.txt', sets the 2D format, and writes the values from the Uinteger32Probe at '/Names/Emitter/Counter'.

```cpp
// Create the file helper.
FileHelper fileHelper;

// Configure the file to be written.
fileHelper.ConfigureFile ("file-helper-example",
                          FileAggregator::FORMATTED);

// Set the labels for this formatted output file.
fileHelper.Set2dFormat ("Time (Seconds) = %.3e\tCount = %.0f");

// Write the values generated by the probe.  The path that we
// provide helps to disambiguate the source of the trace.
fileHelper.WriteProbe ("ns3::Uinteger32Probe",
                       "/Names/Emitter/Counter",
                       "Output");

```

--------------------------------

### Use GtkConfigStore to configure defaults and attributes

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Usage is almost the same as the non-GTK version, but there are no ConfigStore attributes involved. Invoke just before entering Simulator::Run(). A GUI pops up to open menus of attributes and launch simulation execution.

```cpp
// Invoke just before entering Simulator::Run ()
GtkConfigStore config;
config.ConfigureDefaults ();
config.ConfigureAttributes ();

```

--------------------------------

### Binding three arguments with MakeBoundCallback

Source: https://www.nsnam.org/docs/release/3.26/manual/singlehtml/index.html

Example of creating a bound callback that binds all three arguments of NotifyEvent.

```cpp
MakeBoundCallback (&NotifyEvent, a1, b1, c1);
```
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