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diff --git a/documentation/poky-ref-manual/development.xml b/documentation/poky-ref-manual/development.xml deleted file mode 100644 index 4b138e0196..0000000000 --- a/documentation/poky-ref-manual/development.xml +++ /dev/null @@ -1,1098 +0,0 @@ -<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" -"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> - -<chapter id="platdev"> -<title>Platform Development with Poky</title> - - <section id="platdev-appdev"> - <title>Software development</title> - <para> - Poky supports several methods of software development. You can use the method that is - best for you. This chapter describes each development method. - </para> - - <section id="platdev-appdev-external-sdk"> - <title>External Development Using the Poky SDK</title> - <para> - The meta-toolchain and meta-toolchain-sdk targets build tarballs that contain toolchains and - libraries suitable for application development outside of Poky. - For information on these targets see the <ulink linkend='ref-images'>Reference: Images</ulink> - appendix. - </para> - <para> - These tarballs unpack into the - <filename class="directory">/opt/poky</filename> directory and contain - a setup script (e.g. - <filename>/opt/poky/environment-setup-i586-poky-linux</filename>), from which - you can source to initialize a suitable environment. Sourcing these files adds the - compiler, QEMU scripts, QEMU binary, a special version of pkgconfig and other - useful utilities to the PATH variable. Variables to assist pkgconfig and - autotools are also defined so that, for example, configure can find pre-generated test - results for tests that need target hardware on which to run. - </para> - <para> - Using the toolchain with autotool-enabled packages is straightforward - just pass the - appropriate host option to configure. - Following is an example: - <literallayout class='monospaced'> - $ ./configure --host=arm-poky-linux-gnueabi - </literallayout> - For other projects it is usually a case of ensuring the cross tools are used: - <literallayout class='monospaced'> - CC=arm-poky-linux-gnueabi-gcc and LD=arm-poky-linux-gnueabi-ld - </literallayout> - </para> - </section> - - <section id="using-the-eclipse-and-anjuta-plug-ins"> - <title>Using the Eclipse and Anjuta Plug-ins</title> - <para> - Yocto Project supports both Anjuta and Eclipse IDE plug-ins to make developing software - easier for the application developer. The plug-ins provide capability - extensions to the graphical IDE allowing for cross compilation, - deployment and execution of the output in a QEMU emulation session. - Support of these plug-ins also allows for cross debugging and - profiling. Additionally, the Eclipse plug-in provides a suite of tools - that allows the developer to perform remote profiling, tracing, collection of - power data, collection of latency data and collection of performance data. - </para> - - <section id="the-eclipse-plug-in"> - <title>The Eclipse Plug-in</title> - <para> - To use the Eclipse plug-in, a toolchain and SDK built by Poky is required along with - the Eclipse Framework (Helios 3.6.1). - To install the plug-in you need to be in the Eclipse IDE and select - the following menu: - <literallayout class='monospaced'> - Help -> Install New Software - </literallayout> - Specify the target URL as <ulink url='http://www.yoctoproject.org/downloads/eclipse-plug-in/'></ulink>. - </para> - <para> - If you want to download the source code for the plug-in you can find it in the Poky - git repository, which has a web interface, and is located at - <ulink url="http://git.pokylinux.org/cgit.cgi/eclipse-poky"></ulink>. - </para> - - <section id="installing-and-setting-up-the-eclipse-ide"> - <title>Installing and Setting up the Eclipse IDE</title> - <para> - If you don't have the Eclipse IDE (Helios 3.6.1) on your system you need to - download and install it from <ulink url="http://www.eclipse.org/downloads"></ulink>. - Choose the Eclipse Classic, which contains the Eclipse Platform, Java Development - Tools (JDT), and the Plug-in Development Environment. - </para> - <note> - <para> - Due to the Java Virtual Machine's garbage collection (GC) process the - permanent generation space (PermGen) is not cleaned up. This space stores - meta-data descriptions of classes. The default value is set too small - and it could trigger an out-of-memory error like the following: - <literallayout class='monospaced'> - Java.lang.OutOfMemoryError: PermGen space - </literallayout> - This error causes the applications to hang. - </para> - </note> - <para> - To fix this issue you can use the <filename>-vmargs</filename> - option when you start Eclipse to increase the size of the permanent generation space: - <literallayout class='monospaced'> - Eclipse -vmargs -XX:PermSize=256M - </literallayout> - </para> - </section> - - <section id="installing-the-yocto-plug-in"> - <title>Installing the Yocto Plug-in</title> - <para> - Once you have the Eclipse IDE installed and configured you need to install the - Yocto plug-in. You do this similar to installing the Eclipse plug-ins in the - previous section. - </para> - <para> - Do the following to install the Yocto plug-in into the Eclipse IDE: - <orderedlist> - <listitem><para>Select the "Help -> Install New Software" item.</para></listitem> - <listitem><para>In the "Work with:" area click "Add..." and enter the URL for - the Yocto plug-in, which is - <ulink url='http://www.yoctoproject.org/downloads/eclipse-plugin/'></ulink></para></listitem> - <listitem><para>Finish out the installation of the update similar to any other - Eclipse plug-in.</para></listitem> - </orderedlist> - </para> - </section> - - <section id="configuring-yocto-eclipse-plug-in"> - <title>Configuring Yocto Eclipse plug-in</title> - <para> - To configure the Yocto Eclipse plug-in you need to select the mode and the - architecture with which you will be working. Start by selecting "Preferences" - from the "Window" menu and then select "Yocto SDK". - </para> - <para> - If you normally will use an installed Yocto - SDK (under <filename>/opt/poky</filename>) select “SDK Root Mode”. Otherwise, if your crosstool chain - and sysroot are within your poky tree, select “Poky Tree Mode”. - If you are in SDK Root Mode you need to provide your poky tree path, for - example, <filename>$<Poky_tree>/build/</filename>. - </para> - <para> - Next, you need to select the architecture. - Use the drop down list and select the architecture that you’ll be primarily - working against. - For target option, select your typical target QEMU vs External hardware. If you - choose QEMU, you’ll need to specify your QEMU kernel file with full path and the - rootfs mount point. Yocto QEMU boots off user mode NFS. - See the <link linkend='platdev-appdev-qemu'>Developing Externally in QEMU</link> section for - how to set it up. - </para> - <para> - To make your settings the defaults for every new Yocto project created using - the Eclipse IDE, simply save the settings. - </para> - </section> - - <section id="using-the-yocto-eclipse-plug-in"> - <title>Using the Yocto Eclipse Plug-in</title> - <para> - As an example, this section shows you how to cross-compile a Yocto C project that - is autotools-based, deploy the project into QEMU, and then run the debugger against it. - You need to configure the project, trigger the <filename> autogen.sh</filename>, build - the image, start QEMU, and then debug. - </para> - <para> - The following steps show how to create a Yocto autotools-based project using a given template: - </para> - <orderedlist> - <listitem><para>Select "File -> New -> Project" to start the wizard.</para></listitem> - <listitem><para>Expand "C/C++" and select "C Project".</para></listitem> - <listitem><para>Click "Next" and select a template (e.g. "Hello World ANSI C Project").</para></listitem> - <listitem><para>Complete the steps to create the new Yocto autotools-based project using - your chosen template.</para></listitem> - </orderedlist> - <para> - By default, the project uses the Yocto preferences settings as defined using the procedure in - <link linkend="configuring-yocto-eclipse-plug-in">the previous section</link>. - If there are any specific setup requirements for the newly created project - you need to reconfigure the Yocto plug-in through the menu selection by doing the following: - </para> - <orderedlist> - <listitem><para>Select the "Project -> Invoke Yocto Tools -> Reconfigure Yocto" menu item.</para></listitem> - <listitem><para>Complete the dialogue to specify the specific toolchain and QEMU setup information.</para></listitem> - </orderedlist> - <para> - To build the project follow these steps: - </para> - <orderedlist> - <listitem><para>Select "Project -> Reconfigure Project" to trigger the - <filename>autogen.sh</filename> command.</para></listitem> - <listitem><para>Select "Project -> Build" to build the project.</para></listitem> - </orderedlist> - <para> - To start QEMU follow these steps: - </para> - <orderedlist> - <listitem><para>Select "Run -> External Tools" and see if there is - a QEMU instance for the desired target. - If one exists, click on the instance to start QEMU. - If your target does not exist, click "External Tools Configuration" and - you should find an instance of QEMU for your architecture - under the entry under "Program".</para></listitem> - <listitem><para>Wait for the boot to complete.</para></listitem> - </orderedlist> - <para> - To deploy your project and start debugging follow these steps: - </para> - <orderedlist> - <listitem><para>Highlight your project in the project explorer.</para></listitem> - <listitem><para>Select "Run -> Debug Configurations" to bring up your remote debugging configuration - in the right-hand window.</para></listitem> - <listitem><para>Expand “C/C++ Remote Application”.</para></listitem> - <listitem><para>Select "projectname_ gdb_target-poky-linux". - You need to be sure there is an entry for the remote target. - If no entry exists, click "New..." to bring up the wizard. - Use the wizard to select TCF and enter the IP address of you remote target in the - “Host name:” field. - Back in the Remote Debug Configure window, specify in the - “Remote Absolute File Path for C/C++ Application” field the absolute path for the program on - the remote target. - By default, the program deploys into the remote target. - If you don't want this behavior then check “Skip download to target path”.</para></listitem> - <listitem><para>Click "Debug” to start the remote debugging session.</para></listitem> - </orderedlist> - </section> - - <section id="using-yocto-eclipse-plug-in-remote-tools-suite"> - <title>Using Yocto Eclipse plug-in Remote Tools Suite</title> - <para> - Remote tools allow you to perform system profiling, kernel tracing, - examine power consumption, and so forth. To see and access the remote tools use the - "Window -> YoctoTools" menu. - </para> - <para> - Once you pick a tool you need to configure it for the remote target. Every tool - needs to have the connection configured. You must select an existing TCF-based - RSE connection to the remote target. If one does not exist, click "New" to create one. - </para> - <para> - Here are some specifics about the remote tools: - <itemizedlist> - <listitem><para>OProfile: Selecting this tool causes the oprofile-server on the remote - target to launch on the local host machine. The oprofile-viewer - must be installed on the local host machine and the oprofile-server must be - installed on the remote target, respectively, in order to use .</para></listitem> - <listitem><para>lttng: Selecting this tool runs "usttrace" on the remote target, transfers - the output data back to the local host machine and uses "lttv-gui" to graphically - display the output. The "lttv-gui" must be installed on the - local host machine to use this tool. - For information on how to use "lttng" to trace an - application, see <ulink url="http://lttng.org/files/ust/manual/ust.html"></ulink>. - <para> - For "Application" you must supply the absolute path name of the application to - be traced by user mode lttng. For example, typing <filename>/path/to/foo" - </filename> triggers "usttrace /path/to/foo" on the - remote target to trace the program <filename>/path/to/foo</filename>. - </para> - <para> - "Argument" is passed to "usttrace" running on the remote target. - </para></para> - </listitem> - <listitem><para>powertop: Selecting this tool runs "powertop" on the - remote target machine and displays the results in a new view called "powertop". - <para> - "Time to gather data(sec):" is the time passed in seconds before data is - gathered from the remote target for analysis. - </para> - <para> - "show pids in wakeups list:" corresponds to the <filename>-p</filename> - argument passed to "powertop". - </para></para> - </listitem> - <listitem><para>latencytop and perf: "latencytop" identifies - system latency, while "perf" monitors the system's performance - counter registers. Selecting either of these tools causes an RSE - terminal view to appear from which you can run the tools. Both tools refresh the - entire screen to display results while they run.</para></listitem> - </itemizedlist> - </para> - </section> - </section> - - <section id="the-anjuta-plug-in"> - <title>The Anjuta Plug-in</title> - <note> - <para> - Support for the Anjuta plug-in ends after Yocto project 0.9 Release. - However, the source code can be downloaded from the git repository listed later in - this section. - The community is free to continue supporting it post 0.9 Release. - </para> - </note> - <para> - An Anjuta IDE plug-in exists to make developing software within the Poky framework - easier for the application developer familiar with that environment. - The plug-in presents a graphical IDE that allows you to cross-compile, cross-debug, - profile, deploy, and execute an application. - </para> - <para> - To use the plug-in, a toolchain and SDK built by Poky, Anjuta, its development headers and the Anjuta - Plug-in are all required. - The Poky Anjuta Plug-in is available to download as a tarball at the OpenedHand - labs <ulink url="http://labs.o-hand.com/anjuta-poky-sdk-plugin/"></ulink> page or - directly from the Poky Git repository located at - <ulink url="git://git.pokylinux.org/anjuta-poky"></ulink>. - You can also access a web interface to the repository at - <ulink url="http://git.pokylinux.org/?p=anjuta-poky.git;a=summary"></ulink>. - </para> - <para> - See the README file contained in the project for more information on - Anjuta dependencies and building the plug-in. - If you want to disable remote gdb debugging, pass the "--disable-gdb-integration" switch when - you configure the plug-in. - </para> - <section id="setting-up-the-anjuta-plugin"> - <title>Setting Up the Anjuta Plug-in</title> - <para> - Follow these steps to set up the plug-in: - <orderedlist> - <listitem><para>Extract the tarball for the toolchain into / as root. - The toolchain will be installed into <filename>/opt/poky</filename>.</para></listitem> - <listitem><para>To use the plug-in, first open or create an existing project. - If you are creating a new project, the "C GTK+" - project type will allow itself to be cross-compiled. - However, you should be aware that this type uses "glade" for the UI.</para></listitem> - <listitem><para>To activate the plug-in, select "Edit -> Preferences" and then choose - "General" from the left hand side. - Choose the "Installed plug-ins" tab, scroll down to "Poky SDK" and - check the box.</para></listitem> - </orderedlist> - The plug-in is now activated but not configured. - </para> - </section> - <section id="configuring-the-anjuta-plugin"> - <title>Configuring the Anjuta Plug-in</title> - <para> - You can find the configuration options for the SDK by choosing the Poky - SDK icon from the left hand side. - You need to define the following options: - <itemizedlist> - <listitem><para>SDK root: If you use an external toolchain you need to set - SDK root, which is the root directory of the SDK's sysroot. - For an i586 SDK directory is <filename>/opt/poky/</filename>. - This directory will contain "bin", "include", "var" and so forth under your - selected target architecture subdirectory - <filename>/opt/poky/sysroot/i586-poky-linux/</filename>. - The cross-compile tools you need are in - <filename>/opt/poky/sysroot/i586-pokysdk-linux/</filename>.</para></listitem> - <listitem><para>Poky root: If you have a local Poky build tree, you need to - set the Poky root, which is the root directory of the poky build tree. - If you build your i586 target architecture under the subdirectory of - <filename>build_x86</filename> within your Poky tree, the Poky root directory - should be <filename>$<poky_tree>/build_x86/</filename>.</para></listitem> - <listitem><para>Target Architecture: This is the cross compile triplet, - for example, "i586-poky-linux". - This target triplet is the prefix extracted from the set up script file's name. - For example, if the script file name is - <filename>/opt/poky/environment-setup-i586-poky-linux</filename> then the extracted target - triplet is "i586-poky-linux".</para></listitem> - <listitem><para>Kernel: Use the file chooser to select the kernel used with QEMU.</para></listitem> - <listitem><para>Root filesystem: Use the file chooser to select the root - filesystem directory. This directory is where you use "poky-extract-sdk" to extract the - poky-image-sdk tarball.</para></listitem> - </itemizedlist> - </para> - </section> - <section id="using-the-anjuta-plug-in"> - <title>Using the Anjuta Plug-in</title> - <para> - The steps in this section show how to cross-compile a project, deploy it into - QEMU, run a debugger against it and then perform a system-wide profile. - <orderedlist> - <listitem><para>Choose "Build -> Run Configure" or "Build -> Run Autogenerate" to run - "configure" or "autogen", respectively for the project. - Either command passes command-line arguments to instruct the - cross-compile.</para></listitem> - <listitem><para>Choose "Build -> Build Project" to build and compile the project. - If you have previously built the project in the same tree without using - the cross-compiler you might find that your project fails to link. - If this is the case, simply select "Build -> Clean Project" to remove the - old binaries. - After you clean the project you can then try building it again.</para></listitem> - <listitem><para>Choose "Tools -> Start QEMU" to start QEMU. - After QEMU starts any error messages will appear in the message view. - Once Poky has fully booted within QEMU you can deploy the project - into it.</para></listitem> - <listitem><para>Once the project is built and you have QEMU running choose - "Tools -> Deploy" to install the package into a temporary - directory and then copy it using "rsync" over SSH into the target. - A progress bar and appropriate messages appear in the message view.</para></listitem> - <listitem><para>To debug a program installed onto the target choose - "Tools -> Debug remote". - Choosing this menu item causes prompts to appear to define the local binary - for debugging and also for the command line used to run on the target. - When you provide the command line be sure to include the full path to the to binary - installed in the target. - When the command line runs a "gdbserver" over SSH is started on the target and - an instance of "cross-gdb" starts in a local terminal. - The instance of "cross-gdb" will be preloaded to connect to the server and use the SDK root to - find symbols. - It also connects to the target and loads in various libraries as well as the - target program. - You should define any breakpoints or watchpoints at this point in the process since you might not - be able to interrupt the execution later. - To stop the debugger on the target choose "Tools -> Stop debugger".</para></listitem> - <listitem><para>It is also possible to execute a command in the target over SSH. - Doing so causes the appropriate environment to be established for execution. - To execute a command choose "Choose Tools -> Run remote". - This selection opens a terminal with the SSH command inside.</para></listitem> - <listitem><para>To perform a system-wide profile against the system running in QEMU choose - "Tools -> Profile remote". - This choice starts up "OProfileUI" with the appropriate parameters to - connect to the server running inside QEMU and also supplies the path - for debug information necessary to get a useful profile.</para></listitem> - </orderedlist> - </para> - </section> - </section> - </section> - - <section id="platdev-appdev-qemu"> - <title>Developing Externally in QEMU</title> - <para> - Running Poky QEMU images is covered in the - <ulink url="http://www.yoctoproject.org/docs/yocto-quick-start/yocto-project-qs.html"> - Yocto Project Quick Start</ulink> in the "A Quick Test Run" section. - </para> - <para> - Poky's QEMU images contain a complete native toolchain. This means - you can develop applications within QEMU similar to the way you would in a normal system. - Using qemux86 on an x86 machine is fast since the - guest and host architectures match. - On the other hand, using qemuarm can be slower but gives - faithful emulation of ARM-specific issues. To speed things up, these - images support using "distcc" to call a cross-compiler outside the - emulated system. If "runqemu" was used to start - QEMU, and "distccd" is present on the host system, any Bitbake cross-compiling - toolchain available from the build system is automatically - used from within QEMU simply by calling "distcc". You can accomplish this by defining the - cross-compiler variable (e.g. <filename>export CC="distcc"</filename>). - Alternatively, if a suitable SDK/toolchain is present in - <filename>/opt/poky</filename> it is also - automatically be used. - </para> - - <para> - There are several options for connecting into the emulated system. - QEMU provides a framebuffer interface that has standard consoles - available. There is also a serial connection available that has a - console to the system running on it and uses standard IP networking. - The images have a dropbear ssh server running with the root password - disabled to allow standard ssh and scp commands to work. The images - also contain an NFS server that exports the guest's root filesystem, which - allows it to be made available to the host. - </para> - </section> - - <section id="platdev-appdev-insitu"> - <title>Developing in Poky Directly</title> - <para> - Working directly in Poky is a fast and effective development technique. - The idea is that you can directly edit files in - <glossterm><link linkend='var-WORKDIR'>WORKDIR</link></glossterm> - or the source directory <glossterm><link linkend='var-S'>S</link></glossterm> - and then force specific tasks to rerun in order to test the changes. - An example session working on the matchbox-desktop package might - look like this: - </para> - - <para> - <literallayout class='monospaced'> - $ bitbake matchbox-desktop - $ sh - $ cd tmp/work/armv5te-poky-linux-gnueabi/matchbox-desktop-2.0+svnr1708-r0/ - $ cd matchbox-desktop-2 - $ vi src/main.c - $ exit - $ bitbake matchbox-desktop -c compile -f - $ bitbake matchbox-desktop - </literallayout> - </para> - - <para> - This example builds the package, changes into the work directory for the package, - changes a file, then recompiles the package. Instead of using "sh" as it is in the example, - you can also use two different terminals. However, the risk of using two terminals - is that a command like "unpack" could destroy the changes you've made to the - work directory. Consequently, you need to work carefully. - </para> - - <para> - It is useful when making changes directly to the work directory files to do - so using "quilt" as detailed in the <link linkend='usingpoky-modifying-packages-quilt'> - modifying packages with quilt</link> section. You can copy the resulting patches - into the recipe directory and use them directly in the <glossterm><link - linkend='var-SRC_URI'>SRC_URI</link></glossterm>. - </para> - <para> - For a review of the skills used in this section see the <link - linkend="usingpoky-components-bitbake">Bitbake</link> and <link - linkend="usingpoky-debugging-taskrunning">Running Specific Tasks</link> Sections. - </para> - </section> - - <section id="platdev-appdev-devshell"> - <title>Developing with 'devshell'</title> - - <para> - When debugging certain commands or even when just editing packages, the - 'devshell' can be a useful tool. - Use a command like the following to start this tool. - </para> - - <para> - <literallayout class='monospaced'> - $ bitbake matchbox-desktop -c devshell - </literallayout> - </para> - - <para> - This command opens a terminal with a shell prompt within the Poky - environment. Consequently, the following occurs: - <itemizedlist> - <listitem><para>The PATH variable includes the cross toolchain.</para></listitem> - <listitem><para>The pkgconfig variables find the correct <filename>.pc</filename> files.</para></listitem> - <listitem><para>"configure" finds the Poky site files as well as any other necessary files.</para></listitem> - </itemizedlist> - Within this environment, you can run "configure" or "compile" commands as if they - were being run by Poky itself. - The working directory also automatically changes to the (<glossterm><link linkend='var-S'>S</link></glossterm>) - directory. - When you are finished, you just exit the shell or close the terminal window. - </para> - - <para> - The default shell used by "devshell" is the gnome-terminal. - You can use other forms of terminal can by setting the <glossterm> - <link linkend='var-TERMCMD'>TERMCMD</link></glossterm> and <glossterm> - <link linkend='var-TERMCMDRUN'>TERMCMDRUN</link></glossterm> variables - in <filename>local.conf</filename>. - For examples of the other options available, see - <filename>meta/conf/bitbake.conf</filename>. - </para> - <para> - An external shell is launched rather than opening directly into the original terminal - window. - This allows easier interaction with Bitbake's multiple threads as well as - for a future client/server split. - Note that "devshell" will still work over X11 forwarding or similar situations. - </para> - - <para> - It is worth remembering that inside "devshell" you need to use the full - compiler name such as <filename>arm-poky-linux-gnueabi-gcc</filename> - instead of just <filename>gcc</filename>. - The same applies to other applications such as gcc, bintuils, libtool and so forth. - Poky will have setup environmental variables such as CC to assist applications, such as make, - find the correct tools. - </para> - </section> - - <section id="platdev-appdev-srcrev"> - <title>Developing within Poky with an External SCM-based Package</title> - - <para> - If you're working on a recipe that pulls from an external SCM it - is possible to have Poky notice new changes added to the - SCM and then build the latest version using them. - This only works for SCMs from which it is possible to get a sensible revision number for changes. - Currently it works for svn, git and bzr repositories. - </para> - - <para> - To enable this behavior simply add <glossterm> - <link linkend='var-SRCREV'>SRCREV</link></glossterm>_pn-<glossterm> - <link linkend='var-PN'>PN</link></glossterm> = "${AUTOREV}" to - <filename>local.conf</filename>, where <glossterm><link linkend='var-PN'>PN</link></glossterm> - is the name of the package for which you want to enable automatic source - revision updating. - </para> - </section> - </section> - -<section id="platdev-gdb-remotedebug"> - <title>Debugging with GDB Remotely</title> - - <para> - GNU Project Debugger (GDB) - allows you to examine running programs to understand and fix problems and - also to perform post-mortem style analysis of program crashes. - GDB is available as a package within Poky and by default is installed in sdk images. - See <ulink url="http://sourceware.org/gdb/"/> for the GDB source. - </para> - <tip><para> - For best results install <filename>-dbg</filename> packages for the applications - you are going to debug. - Doing so makes available extra debug symbols that will give you more meaningful output. - </para></tip> - - <para> - Sometimes, due to memory or disk space constraints, it is not possible - to use GDB directly on the remote target to debug applications. - These constraints arise because GDB needs to load the debugging information and the - binaries of the process being debugged. - Additionally, GDB needs to perform many computations to locate information such as function - names, variable names and values, stack traces and so forth - even before starting the - debugging process. - These extra computations place more load on the target system and can alter the - characteristics of the program being debugged. - </para> - <para> - To help get past these constraints you can use GDBSERVER. - It runs on the remote target and does not load any debugging information - from the debugged process. - Instead, a GDB instance processes the debugging information that is run on a - remote computer - the host GDB. - The host GDB then sends control commands to GDBSERVER to make it stop or start the debugged - program, as well as read or write memory regions of that debugged - program. - All the debugging information loaded and processed as well - as all the heavy debugging is done by the host GDB. - Offloading these processes gives the GDBSERVER running on the target a chance to remain - small and fast. - </para> - <para> - Because the host GDB is responsible for loading the debugging information and - for doing the necessary processing to make actual debugging happen, the - user has to make sure the host can access the unstripped binaries complete - with their debugging information and also compiled with no optimizations. - The host GDB must also have local access to all the libraries used by the - debugged program. - Because GDBSERVER does not need any local debugging information the binaries on - the remote target can remain stripped. - However, the binaries must also be compiled without optimization - so they match the host's binaries. - </para> - - <para> - To remain consistent with GDB documentation and terminology the binary being debugged - on the remote target machine is referred to as the 'inferior' binary. - For documentation on GDB see the GDB site at - <ulink url="http://sourceware.org/gdb/documentation/">on their site</ulink>. - </para> - - <section id="platdev-gdb-remotedebug-launch-gdbserver"> - <title>Launching GDBSERVER on the Target</title> - <para> - First, make sure GDBSERVER is installed on the target. If not, - install the package <filename>gdbserver</filename>, which needs the - <filename>libthread-db1</filename> package. - </para> - <para> - As an example, to launch GDBSERVER on the target and make it ready to "debug" a - program located at <filename>/path/to/inferior</filename>, connect - to the target and launch: - <literallayout class='monospaced'> - $ gdbserver localhost:2345 /path/to/inferior - </literallayout> - GDBSERVER should now be listening on port 2345 for debugging - commands coming from a remote GDB process that is running on the host computer. - Communication between GDBSERVER and the host GDB are done using TCP. - To use other communication protocols please refer to the GDBSERVER documentation. - </para> - </section> - - <section id="platdev-gdb-remotedebug-launch-gdb"> - <title>Launching GDB on the Host Computer</title> - - <para> - Running GDB on the host computer takes a number of stages. - This section describes those stages. - </para> - - <section id="platdev-gdb-remotedebug-launch-gdb-buildcross"> - <title>Building the Cross-GDB Package</title> |