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[tutorial] Introduce more waf options and best work practices.

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This commit is contained in:
Peter D. Barnes, Jr.
2014-02-04 16:14:44 -08:00
parent 900d3ace25
commit 8d73d7448e
1 changed files with 315 additions and 192 deletions
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doc/tutorial/source/getting-started.rst
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@@ -33,8 +33,8 @@ from the main web site. The second is to fetch and build development
copies of |ns3|. We'll walk through both examples since the tools
involved are slightly different.
Downloading ns-3
****************
Downloading |ns3|
*****************
The |ns3| system as a whole is a fairly complex system and has a
number of dependencies on other components. Along with the systems you will
@@ -72,8 +72,8 @@ The simplest way to get started using Mercurial repositories is to use the
downloading and building of various subsystems of |ns3| for you. We
recommend that you begin your |ns3| work in this environment.
Downloading ns-3 Using a Tarball
++++++++++++++++++++++++++++++++
Downloading |ns3| Using a Tarball
+++++++++++++++++++++++++++++++++
A tarball is a particular format of software archive where multiple
files are bundled together and the archive possibly compressed.
@@ -85,27 +85,24 @@ Let's assume that you, as a user, wish to build |ns3| in a local
directory called ``workspace``.
If you adopt the ``workspace`` directory approach, you can
get a copy of a release by typing the following into your Linux shell
(substitute the appropriate version numbers, of course):
::
(substitute the appropriate version numbers, of course)::
$ cd
$ mkdir workspace
$ cd workspace
$ wget http://www.nsnam.org/releases/ns-allinone-3.17.tar.bz2
$ tar xjf ns-allinone-3.17.tar.bz2
$ wget http://www.nsnam.org/releases/ns-allinone-3.20.tar.bz2
$ tar xjf ns-allinone-3.20.tar.bz2
If you change into the directory ``ns-allinone-3.17`` you should see a
number of files:
If you change into the directory ``ns-allinone-3.20`` you should see a
number of files::
::
bake constants.py ns-3.17 README
$ ls
bake constants.py ns-3.20 README
build.py netanim-3.103 pybindgen-0.16.0.825 util.py
You are now ready to build the |ns3| distribution.
Downloading ns-3 Using Bake
Downloading |ns3| Using Bake
++++++++++++++++++++++++++++
Bake is a tool for distributed integration and building,
@@ -119,9 +116,7 @@ directory under which one can keep local Mercurial repositories.
Any directory name will do, but we'll assume that ``workspace`` is used
herein (note: ``repos`` may also be used in some documentation as
an example directory name). You can get a copy of ``bake`` by typing the
following into your Linux shell (assuming you have installed Mercurial):
::
following into your Linux shell (assuming you have installed Mercurial)::
$ cd
$ mkdir workspace
@@ -133,6 +128,7 @@ following displayed,
::
...
destination directory: bake
requesting all changes
adding changesets
@@ -143,10 +139,9 @@ following displayed,
45 files updated, 0 files merged, 0 files removed, 0 files unresolved
After the clone command completes, you should have a directory called
``bake``, the contents of which should look something like the following:
::
``bake``, the contents of which should look something like the following::
$ ls
bake bakeconf.xml doc generate-binary.py TODO
bake.py examples test
@@ -157,10 +152,10 @@ distribution of your choice.
There are a few configuration targets available:
1. ``ns-3.17``: the module corresponding to the release; it will download
1. ``ns-3.20``: the module corresponding to the release; it will download
components similar to the release tarball.
2. ``ns-3-dev``: a similar module but using the development code tree
3. ``ns-allinone-3.17``: the module that includes other optional features
3. ``ns-allinone-3.20``: the module that includes other optional features
such as click routing, openflow for |ns3|, and the Network Simulation
Cradle
4. ``ns-3-allinone``: similar to the released version of the allinone
@@ -178,7 +173,7 @@ code either by inspection of the repository list or by going to the
`"ns-3 Releases"
<http://www.nsnam.org/releases>`_
web page and clicking on the latest release link. We'll proceed in
this tutorial example with ``ns-3.17``.
this tutorial example with ``ns-3.20``.
We are now going to use the bake tool to pull down the various pieces of
|ns3| you will be using. First, we'll say a word about running bake.
@@ -187,9 +182,7 @@ bake works by downloading source packages into a source directory,
and installing libraries into a build directory. bake can be run
by referencing the binary, but if one chooses to run bake from
outside of the directory it was downloaded into, it is advisable
to put bake into your path, such as follows (Linux bash shell example):
::
to put bake into your path, such as follows (Linux bash shell example)::
$ export BAKE_HOME=`pwd`/bake
$ export PATH=$PATH:$BAKE_HOME
@@ -199,16 +192,12 @@ However, setting environment variables is not strictly necessary to
complete this tutorial, so we'll call bake directly by specifying the path
to it in our shell commands.
Step into the workspace directory and type the following into your shell:
Step into the workspace directory and type the following into your shell::
::
$ ./bake.py configure -e ns-3.17
$ ./bake.py configure -e ns-3.20
Next, we'l ask bake to check whether we have enough tools to download
various components. Type:
::
various components. Type::
$ ./bake.py check
@@ -240,15 +229,11 @@ In particular, download tools such as Mercurial, CVS, GIT, and Bazaar
are our principal concerns at this point, since they allow us to fetch
the code. Please install missing tools at this stage if you are able to.
Next, try to download the software:
Next, try to download the software::
::
$ ./bake.py download
./bake.py download
should yield something like:
::
should yield something like::
>> Searching for system dependency pygoocanvas - OK
>> Searching for system dependency python-dev - OK
@@ -257,22 +242,21 @@ should yield something like:
>> Searching for system dependency g++ - OK
>> Searching for system dependency qt4 - OK
>> Downloading netanim-3.103 - OK
>> Downloading ns-3.17 - OK
>> Downloading ns-3.20 - OK
The above suggests that three sources have been downloaded. Check the
``source`` directory now and type ``ls``; one should see:
``source`` directory now and type ``ls``; one should see::
::
netanim-3.103 ns-3.17 pybindgen-0.16.0.825
$ ls
netanim-3.103 ns-3.20 pybindgen-0.16.0.825
You are now ready to build the |ns3| distribution.
Building ns-3
*************
Building |ns3|
**************
Building with build.py
++++++++++++++++++++++
Building with ``build.py``
++++++++++++++++++++++++++
When working from a released tarball, the first time you build the
|ns3| project you can build using a convenience program found in the
``allinone`` directory. This program is called ``build.py``. This
@@ -283,10 +267,8 @@ native |ns3| build system, Waf, to be introduced later in this tutorial.
If you downloaded
using a tarball you should have a directory called something like
``ns-allinone-3.17`` under your ``~/workspace`` directory.
Type the following:
::
``ns-allinone-3.20`` under your ``~/workspace`` directory.
Type the following::
$ ./build.py --enable-examples --enable-tests
@@ -299,11 +281,9 @@ are not necessary for your work, if you wish.
You will see lots of typical compiler output messages displayed as the build
script builds the various pieces you downloaded. Eventually you should see the
following magic words:
following magic words::
::
Waf: Leaving directory `/path/to/workspace/ns-allinone-3.17/ns-3.17/build'
Waf: Leaving directory `/path/to/workspace/ns-allinone-3.20/ns-3.20/build'
'build' finished successfully (6m25.032s)
Modules built:
@@ -325,17 +305,15 @@ following magic words:
brite click openflow
visualizer
Leaving directory `./ns-3.17'
Leaving directory `./ns-3.20'
Regarding the portion about modules not built:
::
Regarding the portion about modules not built::
Modules not built (see ns-3 tutorial for explanation):
brite click openflow
visualizer
This just means that some ns-3 modules that have dependencies on
This just means that some |ns3| modules that have dependencies on
outside libraries may not have been built, or that the configuration
specifically asked not to build them. It does not mean that the
simulator did not build successfully or that it will provide wrong
@@ -351,20 +329,16 @@ may continue to use it to build |ns3|. Type
$ ./bake.py build
and you should see something like:
::
and you should see something like::
>> Building pybindgen-0.16.0.825 - OK
>> Building netanim-3.103 - OK
>> Building ns-3.17 - OK
>> Building ns-3.20 - OK
*Hint: you can also perform both steps, download and build by calling 'bake.py deploy'.*
If there happens to be a failure, please have a look at what the following
command tells you; it may give a hint as to a missing dependency:
::
command tells you; it may give a hint as to a missing dependency::
$ ./bake.py show
@@ -390,83 +364,96 @@ build the optimized version of the code. By default you have configured
your project to build the debug version. Let's tell the project to
make an optimized build. To explain to Waf that it should do optimized
builds that include the examples and tests, you will need to execute the
following commands,
::
following commands::
$ ./waf clean
$ ./waf -d optimized --enable-examples --enable-tests configure
$ ./waf --build-profile=optimized --enable-examples --enable-tests configure
This runs Waf out of the local directory (which is provided as a convenience
for you). The first command to clean out the previous build is not
typically strictly necessary but is good practice; it will remove the
typically strictly necessary but is good practice (but see `Build Profiles`_,
below); it will remove the
previously built libraries and object files found in directory ``build/``.
When the project is reconfigured and the build system checks for various
dependencies, you should see
output that looks similar to the following,
output that looks similar to the following::
::
Checking for program g++ : ok /usr/bin/g++
Checking for program cpp : ok /usr/bin/cpp
Checking for program ar : ok /usr/bin/ar
Checking for program ranlib : ok /usr/bin/ranlib
Checking for g++ : ok
Checking for program pkg-config : ok /usr/bin/pkg-config
Checking for -Wno-error=deprecated-declarations support : yes
Checking for -Wl,--soname=foo support : yes
Checking for header stdlib.h : ok
Checking for header signal.h : ok
Checking for header pthread.h : ok
Checking for high precision time implementation : 128-bit integer
Checking for header stdint.h : ok
Checking for header inttypes.h : ok
Checking for header sys/inttypes.h : not found
Checking for library rt : ok
Checking for header netpacket/packet.h : ok
Checking for pkg-config flags for GSL : ok
Checking for header linux/if_tun.h : ok
Checking for pkg-config flags for GTK_CONFIG_STORE : ok
Checking for pkg-config flags for LIBXML2 : ok
Checking for library sqlite3 : ok
Checking for NSC location : ok ../nsc (guessed)
Checking for library dl : ok
Checking for NSC supported architecture x86_64 : ok
Checking for program python : ok /usr/bin/python
Checking for Python version >= 2.3 : ok 2.5.2
Checking for library python2.5 : ok
Checking for program python2.5-config : ok /usr/bin/python2.5-config
Checking for header Python.h : ok
Checking for -fvisibility=hidden support : yes
Checking for pybindgen location : ok ../pybindgen (guessed)
Checking for Python module pybindgen : ok
Checking for pybindgen version : ok 0.10.0.640
Checking for Python module pygccxml : ok
Checking for pygccxml version : ok 0.9.5
Checking for program gccxml : ok /usr/local/bin/gccxml
Checking for gccxml version : ok 0.9.0
Checking for program sudo : ok /usr/bin/sudo
Checking for program hg : ok /usr/bin/hg
Checking for program valgrind : ok /usr/bin/valgrind
Setting top to : .
Setting out to : build
Checking for 'gcc' (c compiler) : /usr/bin/gcc
Checking for cc version : 4.2.1
Checking for 'g++' (c++ compiler) : /usr/bin/g++
Checking boost includes : 1_46_1
Checking boost libs : ok
Checking for boost linkage : ok
Checking for click location : not found
Checking for program pkg-config : /sw/bin/pkg-config
Checking for 'gtk+-2.0' >= 2.12 : yes
Checking for 'libxml-2.0' >= 2.7 : yes
Checking for type uint128_t : not found
Checking for type __uint128_t : yes
Checking high precision implementation : 128-bit integer (default)
Checking for header stdint.h : yes
Checking for header inttypes.h : yes
Checking for header sys/inttypes.h : not found
Checking for header sys/types.h : yes
Checking for header sys/stat.h : yes
Checking for header dirent.h : yes
Checking for header stdlib.h : yes
Checking for header signal.h : yes
Checking for header pthread.h : yes
Checking for header stdint.h : yes
Checking for header inttypes.h : yes
Checking for header sys/inttypes.h : not found
Checking for library rt : not found
Checking for header netpacket/packet.h : not found
Checking for header sys/ioctl.h : yes
Checking for header net/if.h : not found
Checking for header net/ethernet.h : yes
Checking for header linux/if_tun.h : not found
Checking for header netpacket/packet.h : not found
Checking for NSC location : not found
Checking for 'mpic++' : yes
Checking for 'sqlite3' : yes
Checking for header linux/if_tun.h : not found
Checking for program sudo : /usr/bin/sudo
Checking for program valgrind : /sw/bin/valgrind
Checking for 'gsl' : yes
Checking for compilation flag -Wno-error=deprecated-d... support : ok
Checking for compilation flag -Wno-error=deprecated-d... support : ok
Checking for compilation flag -fstrict-aliasing... support : ok
Checking for compilation flag -fstrict-aliasing... support : ok
Checking for compilation flag -Wstrict-aliasing... support : ok
Checking for compilation flag -Wstrict-aliasing... support : ok
Checking for program doxygen : /usr/local/bin/doxygen
---- Summary of optional NS-3 features:
Threading Primitives : enabled
Real Time Simulator : enabled
Emulated Net Device : enabled
GNU Scientific Library (GSL) : enabled
Tap Bridge : enabled
Build profile : debug
Build directory : build
Python Bindings : enabled
BRITE Integration : not enabled (BRITE not enabled (see option --with-brite))
NS-3 Click Integration : not enabled (nsclick not enabled (see option --with-nsclick))
GtkConfigStore : enabled
XmlIo : enabled
Threading Primitives : enabled
Real Time Simulator : enabled (librt is not available)
Emulated Net Device : enabled (<netpacket/packet.h> include not detected)
File descriptor NetDevice : enabled
Tap FdNetDevice : not enabled (needs linux/if_tun.h)
Emulation FdNetDevice : not enabled (needs netpacket/packet.h)
PlanetLab FdNetDevice : not enabled (PlanetLab operating system not detected (see option --force-planetlab))
Network Simulation Cradle : not enabled (NSC not found (see option --with-nsc))
MPI Support : enabled
NS-3 OpenFlow Integration : not enabled (Required boost libraries not found, missing: system, signals, filesystem)
SQlite stats data output : enabled
Network Simulation Cradle : enabled
Python Bindings : enabled
Python API Scanning Support : enabled
Tap Bridge : not enabled (<linux/if_tun.h> include not detected)
PyViz visualizer : enabled
Use sudo to set suid bit : not enabled (option --enable-sudo not selected)
Build tests : enabled
Build examples : enabled
Static build : not enabled (option --enable-static not selected)
'configure' finished successfully (2.870s)
GNU Scientific Library (GSL) : enabled
'configure' finished successfully (1.944s)
Note the last part of the above output. Some ns-3 options are not enabled by
Note the last part of the above output. Some |ns3| options are not enabled by
default or require support from the underlying system to work properly.
For instance, to enable XmlTo, the library libxml-2.0 must be found on the
system. If this library were not found, the corresponding |ns3| feature
@@ -479,7 +466,7 @@ Now go ahead and switch back to the debug build that includes the examples and t
::
$ ./waf clean
$ ./waf -d debug --enable-examples --enable-tests configure
$ ./waf --build-profile=debug --enable-examples --enable-tests configure
The build system is now configured and you can build the debug versions of
the |ns3| programs by simply typing
@@ -492,72 +479,146 @@ Okay, sorry, I made you build the |ns3| part of the system twice,
but now you know how to change the configuration and build optimized code.
Here are a few more introductory tips about Waf.
Some waf commands are meaningful during the build phase and some commands are valid
in the configuration phase. For example, if you wanted to use the emulation
Configure vs. Build
===================
Some Waf commands are only meaningful during the configure phase and some commands are valid
in the build phase. For example, if you wanted to use the emulation
features of |ns3|, you might want to enable setting the suid bit using
sudo as described above. This turns out to be a configuration-time command, and so
you could reconfigure using the following command that also includes the examples and tests
you could reconfigure using the following command that also includes the examples and tests.
::
$ ./waf configure -d debug --enable-sudo --enable-examples --enable-tests
$ ./waf configure --enable-sudo --enable-examples --enable-tests
If you do this, waf will have run sudo to change the socket creator programs of the
emulation code to run as root. There are many other configure- and build-time options
available in waf. To explore these options, type:
If you do this, Waf will have run sudo to change the socket creator programs of the
emulation code to run as root.
::
There are many other configure- and build-time options
available in Waf. To explore these options, type::
$ ./waf --help
We'll use some of the testing-related commands in the next section.
Finally, as an aside, it is possible to specify that waf builds the
project in
a directory different than the default ``build/`` directory by passing
the ``-o`` option to configure; e.g.
Build Profiles
==============
We already saw how you can configure Waf for ``debug`` or ``optimized`` builds::
$ ./waf --build-profile=debug
There is also an intermediate build profile, ``release``. ``-d`` is a
synonym for ``--build-profile``.
By default Waf puts the build artifacts in the ``build`` directory.
You can specify a different output directory with the ``--out``
option, e.g.
::
$ ./waf configure -d debug -o build/debug --enable-examples --enable-tests
$ ./waf configure --out=foo
This allows users to work with multiple builds rather than always
overwriting the last build.
Combining this with build profiles lets you switch between the different
compile options in a clean way::
In the examples above, waf uses GCC C++ compiler, command ``g++``, for
building ns-3. However, it's possible to change C++ compiler used by waf.
Say one wants to use Clang C++ compiler, command ``clang++``; it's done by
$ ./waf configure --build-profile=debug --out=build/debug
$ ./waf build
...
$ ./waf configure --build-profile=optimized --out=build/optimized
$ ./waf build
...
This allows you to work with multiple builds rather than always
overwriting the last build. When you switch, Waf will only compile
what it has to, instead of recompiling everything.
When you do switch build profiles like this, you have to be careful
to give the same configuration parameters each time. It may be convenient
to define some environment variables to help you avoid mistakes::
$ export NS3CONFIG="--enable-examples --enable-tests"
$ export NS3DEBUG="--build-profile=debug --out=build/debug"
$ export NS3OPT=="--build-profile=optimized --out=build/optimized"
$ ./waf configure $NS3CONFIG $NS3DEBUG
$ ./waf build
...
$ ./waf configure $NS3CONFIG $NS3OPT
$ ./waf build
Compilers
=========
In the examples above, Waf uses the GCC C++ compiler, ``g++``, for
building |ns3|. However, it's possible to change the C++ compiler used by Waf
by defining the ``CXX`` environment variable.
For example, to use the Clang C++ compiler, ``clang++``,
::
$ CXX="clang++" ./waf configure
$ ./waf build
One can also set up waf to do distributed compilation with ``distcc`` in
a similar way:
::
One can also set up Waf to do distributed compilation with ``distcc`` in
a similar way::
$ CXX="distcc g++" ./waf configure
$ ./waf build
More info on distcc and distributed compilation can be found on it's
More info on ``distcc`` and distributed compilation can be found on it's
`project page
<http://code.google.com/p/distcc/>`_
under Documentation section.
Testing ns-3
************
One Waf
=======
There is only one Waf script, at the top level of the |ns3| source tree.
As you work, you may find yourself spending a lot of time in ``scratch/``,
or deep in ``src/...``, and needing to invoke Waf. You could just
remember where you are, and invoke Waf like this::
$ ../../../waf ...
but that get's tedious, and error prone, and there are better solutions.
If you have the full |ns3| repository this little gem is a start::
$ cd $(hg root) && ./waf ...
Even better is to define this as a shell function::
$ function waff { cd $(hg root) && ./waf $* ; }
$ waff build
If you only have the tarball, an environment variable can help::
$ export NS3DIR="$PWD"
$ function waff { cd $NS3DIR && ./waf $* ; }
$ cd scratch
$ waff build
It might be tempting in a module directory to add a trivial ``waf``
script along the lines of ``exec ../../waf``. Please don't. It's
confusing to new-comers, and when done poorly it leads to subtle build
errors. The solutions above are the way to go.
Testing |ns3|
*************
You can run the unit tests of the |ns3| distribution by running the
"./test.py -c core" script,
::
``./test.py -c core`` script::
$ ./test.py -c core
These tests are run in parallel by waf. You should eventually
see a report saying that,
These tests are run in parallel by Waf. You should eventually
see a report saying that
::
@@ -565,9 +626,8 @@ see a report saying that,
This is the important message.
You will also see output from the test runner and the output will actually look something like,
::
You will also see the summary output from Waf and the test runner
executing each test, which will actually look something like::
Waf: Entering directory `/path/to/workspace/ns-3-allinone/ns-3-dev/build'
Waf: Leaving directory `/path/to/workspace/ns-3-allinone/ns-3-dev/build'
@@ -590,34 +650,26 @@ You will also see output from the test runner and the output will actually look
PASS: TestSuite ns3-wifi-interference
PASS: TestSuite histogram
PASS: TestSuite sample
PASS: TestSuite ipv4-address-helper
PASS: TestSuite devices-wifi
PASS: TestSuite propagation-loss-model
...
PASS: TestSuite attributes
PASS: TestSuite config
PASS: TestSuite global-value
PASS: TestSuite command-line
PASS: TestSuite basic-random-number
PASS: TestSuite object
PASS: TestSuite random-number-generators
92 of 92 tests passed (92 passed, 0 failed, 0 crashed, 0 valgrind errors)
This command is typically run by users to quickly verify that an
|ns3| distribution has built correctly.
|ns3| distribution has built correctly. (Note the order of the ``PASS: ...``
lines can vary, which is okay. What's important is that the summary line at
the end report that all tests passed; none failed or crashed.)
Running a Script
****************
We typically run scripts under the control of Waf. This allows the build
system to ensure that the shared library paths are set correctly and that
the libraries are available at run time. To run a program, simply use the
``--run`` option in Waf. Let's run the |ns3| equivalent of the
ubiquitous hello world program by typing the following:
::
ubiquitous hello world program by typing the following::
$ ./waf --run hello-simulator
@@ -629,28 +681,26 @@ produces the following output.
Hello Simulator
*Congratulations. You are now an ns-3 user.*
Congratulations! You are now an ns-3 user!
*What do I do if I don't see the output?*
**What do I do if I don't see the output?**
If you see ``waf`` messages indicating that the build was
If you see Waf messages indicating that the build was
completed successfully, but do not see the "Hello Simulator" output,
chances are that you have switched your build mode to "optimized" in
the "Building with Waf" section, but have missed the change back to
"debug" mode. All of the console output used in this tutorial uses a
chances are that you have switched your build mode to ``optimized`` in
the `Building with Waf`_ section, but have missed the change back to
``debug`` mode. All of the console output used in this tutorial uses a
special |ns3| logging component that is useful for printing
user messages to the console. Output from this component is
automatically disabled when you compile optimized code -- it is
"optimized out." If you don't see the "Hello Simulator" output,
type the following,
type the following::
::
$ ./waf configure --build-profile=debug --enable-examples --enable-tests
$ ./waf configure -d debug --enable-examples --enable-tests
to tell ``waf`` to build the debug versions of the |ns3|
to tell Waf to build the debug versions of the |ns3|
programs that includes the examples and tests. You must still build
the actual debug version of the code by typing,
the actual debug version of the code by typing
::
@@ -659,7 +709,80 @@ the actual debug version of the code by typing,
Now, if you run the ``hello-simulator`` program, you should see the
expected output.
If you want to run programs under another tool such as gdb or valgrind,
see this `wiki entry
<http://www.nsnam.org/wiki/User_FAQ#How_to_run_NS-3_programs_under_another_tool>`_.
Program Arguments
+++++++++++++++++
To feed command line arguments to an |ns3| program use this pattern::
$ ./waf --run <ns3-program> --command-template="%s <args>"
Substitute your program name for ``<ns3-program>``, and the arguments
for ``<args>``. The ``--command-template`` argument to Waf is
basically a recipe for constructing the actual command line Waf should use
to execute the program. Waf checks that the build is complete,
sets the shared library paths, then invokes the executable
using the provided command line template,
inserting the program name for the ``%s`` placeholder.
(I admit this is a bit awkward, but that's the way it is. Patches welcome!)
Another particularly useful example is to run the ``mytest`` test suite
by itself. Above, we used the ``./test.py`` script to run a whole slew of
tests in parallel, by repeatedly invoking the real testing program,
``test-runner``. To invoke ``test-runner`` directly for a single test::
$ ./waf --run test-runner --command-template="% --suite=mytest --verbose"
This passes the arguments to the ``test-runner`` program. To print the
available ``test-runner`` options::
$ ./waf --run test-runner --command-template="% --help"
Debugging
+++++++++
To run |ns3| programs under the control of another utility, such as
a debugger (*e.g.* ``gdb``) or memory checker (*e.g.* ``valgrind``),
you use a similar ``--command-template="..."`` form.
For example, to run your |ns3| program ``mysim`` with the arguments
``<args>`` under the ``gdb`` debugger::
$ ./waf --run=hello-simulator --command-template="gdb %s --args <args>"
Notice that the |ns3| program name goes with the ``--run`` argument,
and the control utility (here ``gdb``) is the first token
in the ``--commmand-template`` argument. The ``--args`` tells ``gdb``
that the remainder of the command line belongs to the "inferior" program.
(Some ``gdb``'s don't understand the ``--args`` feature. In this case,
omit the program arguments from the ``--command-template``,
and use the ``gdb`` command ``set args``.)
We can combine this recipe and the previous one to run a test under the
debugger::
$ ./waf --run test-runner --command-template="gdb %s --args --suite=mytest --verbose"
Working Directory
+++++++++++++++++
Waf needs to run from it's location at the top of the |ns3| tree.
This becomes the working directory where output files will be written.
But what if you want to keep those ouf to the |ns3| source tree? Use
the ``--cwd`` argument::
$ ./waf --cwd=...
It may be more convenient to start with your working directory where
you want the output files, in which case a little indirection can help::
$ function waff {
CWD="$PWD"
cd $NS3DIR >/dev/null
./waf --cwd="$CWD" $*
cd - >/dev/null
}
This embellishment of the previous version saves the current working directory,
``cd``'s to the Waf directory, then instructs Waf to change the working
directory *back* to the saved current working directory before running the
program.