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| <h3 class="heading">gdbserver man</h3> |
| |
| <!-- man title gdbserver Remote Server for the GNU Debugger --> |
| <pre class="format"><!-- man begin SYNOPSIS gdbserver --> |
| gdbserver <var>comm</var> <var>prog</var> [<var>args</var><small class="dots">...</small>] |
| |
| gdbserver –attach <var>comm</var> <var>pid</var> |
| |
| gdbserver –multi <var>comm</var> |
| <!-- man end --> |
| </pre> |
| <!-- man begin DESCRIPTION gdbserver --> |
| <p><samp><span class="command">gdbserver</span></samp> is a program that allows you to run <span class="sc">gdb</span> on a different machine |
| than the one which is running the program being debugged. |
| |
| <h4 class="subheading">Usage (server (target) side)</h4> |
| |
| <p>First, you need to have a copy of the program you want to debug put onto |
| the target system. The program can be stripped to save space if needed, as |
| <samp><span class="command">gdbserver</span></samp> doesn't care about symbols. All symbol handling is taken care of by |
| the <span class="sc">gdb</span> running on the host system. |
| |
| <p>To use the server, you log on to the target system, and run the <samp><span class="command">gdbserver</span></samp> |
| program. You must tell it (a) how to communicate with <span class="sc">gdb</span>, (b) the name of |
| your program, and (c) its arguments. The general syntax is: |
| |
| <pre class="smallexample"> target> gdbserver <var>comm</var> <var>program</var> [<var>args</var> ...] |
| </pre> |
| <p>For example, using a serial port, you might say: |
| |
| <pre class="smallexample"> target> gdbserver <samp><span class="file">/dev/com1</span></samp> emacs foo.txt |
| </pre> |
| <p>This tells <samp><span class="command">gdbserver</span></samp> to debug emacs with an argument of foo.txt, and |
| to communicate with <span class="sc">gdb</span> via <samp><span class="file">/dev/com1</span></samp>. <samp><span class="command">gdbserver</span></samp> now |
| waits patiently for the host <span class="sc">gdb</span> to communicate with it. |
| |
| <p>To use a TCP connection, you could say: |
| |
| <pre class="smallexample"> target> gdbserver host:2345 emacs foo.txt |
| </pre> |
| <p>This says pretty much the same thing as the last example, except that we are |
| going to communicate with the <code>host</code> <span class="sc">gdb</span> via TCP. The <code>host:2345</code> argument means |
| that we are expecting to see a TCP connection from <code>host</code> to local TCP port |
| 2345. (Currently, the <code>host</code> part is ignored.) You can choose any number you |
| want for the port number as long as it does not conflict with any existing TCP |
| ports on the target system. This same port number must be used in the host |
| <span class="sc">gdb</span>s <code>target remote</code> command, which will be described shortly. Note that if |
| you chose a port number that conflicts with another service, <samp><span class="command">gdbserver</span></samp> will |
| print an error message and exit. |
| |
| <p><samp><span class="command">gdbserver</span></samp> can also attach to running programs. |
| This is accomplished via the <samp><span class="option">--attach</span></samp> argument. The syntax is: |
| |
| <pre class="smallexample"> target> gdbserver --attach <var>comm</var> <var>pid</var> |
| </pre> |
| <p><var>pid</var> is the process ID of a currently running process. It isn't |
| necessary to point <samp><span class="command">gdbserver</span></samp> at a binary for the running process. |
| |
| <p>To start <code>gdbserver</code> without supplying an initial command to run |
| or process ID to attach, use the <samp><span class="option">--multi</span></samp> command line option. |
| In such case you should connect using <kbd>target extended-remote</kbd> to start |
| the program you want to debug. |
| |
| <pre class="smallexample"> target> gdbserver --multi <var>comm</var> |
| </pre> |
| <h4 class="subheading">Usage (host side)</h4> |
| |
| <p>You need an unstripped copy of the target program on your host system, since |
| <span class="sc">gdb</span> needs to examine its symbol tables and such. Start up <span class="sc">gdb</span> as you normally |
| would, with the target program as the first argument. (You may need to use the |
| <samp><span class="option">--baud</span></samp> option if the serial line is running at anything except 9600 baud.) |
| That is <code>gdb TARGET-PROG</code>, or <code>gdb --baud BAUD TARGET-PROG</code>. After that, the only |
| new command you need to know about is <code>target remote</code> |
| (or <code>target extended-remote</code>). Its argument is either |
| a device name (usually a serial device, like <samp><span class="file">/dev/ttyb</span></samp>), or a <code>HOST:PORT</code> |
| descriptor. For example: |
| |
| <pre class="smallexample"> (gdb) target remote <samp><span class="file">/dev/ttyb</span></samp> |
| </pre> |
| <p class="noindent">communicates with the server via serial line <samp><span class="file">/dev/ttyb</span></samp>, and: |
| |
| <pre class="smallexample"> (gdb) target remote the-target:2345 |
| </pre> |
| <p class="noindent">communicates via a TCP connection to port 2345 on host `the-target', where |
| you previously started up <samp><span class="command">gdbserver</span></samp> with the same port number. Note that for |
| TCP connections, you must start up <samp><span class="command">gdbserver</span></samp> prior to using the `target remote' |
| command, otherwise you may get an error that looks something like |
| `Connection refused'. |
| |
| <p><samp><span class="command">gdbserver</span></samp> can also debug multiple inferiors at once, |
| described in |
| <a href="Inferiors-and-Programs.html#Inferiors-and-Programs">Inferiors and Programs</a>. |
| In such case use the <code>extended-remote</code> <span class="sc">gdb</span> command variant: |
| |
| <pre class="smallexample"> (gdb) target extended-remote the-target:2345 |
| </pre> |
| <p>The <samp><span class="command">gdbserver</span></samp> option <samp><span class="option">--multi</span></samp> may or may not be used in such |
| case. |
| <!-- man end --> |
| |
| <!-- man begin OPTIONS gdbserver --> |
| <p>There are three different modes for invoking <samp><span class="command">gdbserver</span></samp>: |
| |
| <ul> |
| <li>Debug a specific program specified by its program name: |
| |
| <pre class="smallexample"> gdbserver <var>comm</var> <var>prog</var> [<var>args</var>...] |
| </pre> |
| <p>The <var>comm</var> parameter specifies how should the server communicate |
| with <span class="sc">gdb</span>; it is either a device name (to use a serial line), |
| a TCP port number (<code>:1234</code>), or <code>-</code> or <code>stdio</code> to use |
| stdin/stdout of <code>gdbserver</code>. Specify the name of the program to |
| debug in <var>prog</var>. Any remaining arguments will be passed to the |
| program verbatim. When the program exits, <span class="sc">gdb</span> will close the |
| connection, and <code>gdbserver</code> will exit. |
| |
| <li>Debug a specific program by specifying the process ID of a running |
| program: |
| |
| <pre class="smallexample"> gdbserver --attach <var>comm</var> <var>pid</var> |
| </pre> |
| <p>The <var>comm</var> parameter is as described above. Supply the process ID |
| of a running program in <var>pid</var>; <span class="sc">gdb</span> will do everything |
| else. Like with the previous mode, when the process <var>pid</var> exits, |
| <span class="sc">gdb</span> will close the connection, and <code>gdbserver</code> will exit. |
| |
| <li>Multi-process mode – debug more than one program/process: |
| |
| <pre class="smallexample"> gdbserver --multi <var>comm</var> |
| </pre> |
| <p>In this mode, <span class="sc">gdb</span> can instruct <samp><span class="command">gdbserver</span></samp> which |
| command(s) to run. Unlike the other 2 modes, <span class="sc">gdb</span> will not |
| close the connection when a process being debugged exits, so you can |
| debug several processes in the same session. |
| </ul> |
| |
| <p>In each of the modes you may specify these options: |
| |
| <dl> |
| <dt><samp><span class="env">--help</span></samp><dd>List all options, with brief explanations. |
| |
| <br><dt><samp><span class="env">--version</span></samp><dd>This option causes <samp><span class="command">gdbserver</span></samp> to print its version number and exit. |
| |
| <br><dt><samp><span class="env">--attach</span></samp><dd><samp><span class="command">gdbserver</span></samp> will attach to a running program. The syntax is: |
| |
| <pre class="smallexample"> target> gdbserver --attach <var>comm</var> <var>pid</var> |
| </pre> |
| <p><var>pid</var> is the process ID of a currently running process. It isn't |
| necessary to point <samp><span class="command">gdbserver</span></samp> at a binary for the running process. |
| |
| <br><dt><samp><span class="env">--multi</span></samp><dd>To start <code>gdbserver</code> without supplying an initial command to run |
| or process ID to attach, use this command line option. |
| Then you can connect using <kbd>target extended-remote</kbd> and start |
| the program you want to debug. The syntax is: |
| |
| <pre class="smallexample"> target> gdbserver --multi <var>comm</var> |
| </pre> |
| <br><dt><samp><span class="env">--debug</span></samp><dd>Instruct <code>gdbserver</code> to display extra status information about the debugging |
| process. |
| This option is intended for <code>gdbserver</code> development and for bug reports to |
| the developers. |
| |
| <br><dt><samp><span class="env">--remote-debug</span></samp><dd>Instruct <code>gdbserver</code> to display remote protocol debug output. |
| This option is intended for <code>gdbserver</code> development and for bug reports to |
| the developers. |
| |
| <br><dt><samp><span class="env">--debug-format=option1[,option2,...]</span></samp><dd>Instruct <code>gdbserver</code> to include extra information in each line |
| of debugging output. |
| See <a href="Other-Command_002dLine-Arguments-for-gdbserver.html#Other-Command_002dLine-Arguments-for-gdbserver">Other Command-Line Arguments for gdbserver</a>. |
| |
| <br><dt><samp><span class="env">--wrapper</span></samp><dd>Specify a wrapper to launch programs |
| for debugging. The option should be followed by the name of the |
| wrapper, then any command-line arguments to pass to the wrapper, then |
| <kbd>--</kbd> indicating the end of the wrapper arguments. |
| |
| <br><dt><samp><span class="env">--once</span></samp><dd>By default, <samp><span class="command">gdbserver</span></samp> keeps the listening TCP port open, so that |
| additional connections are possible. However, if you start <code>gdbserver</code> |
| with the <samp><span class="option">--once</span></samp> option, it will stop listening for any further |
| connection attempts after connecting to the first <span class="sc">gdb</span> session. |
| |
| <!-- disable-packet is not documented for users. --> |
| <!-- disable-randomization and -no-disable-randomization are superseded by --> |
| <!-- QDisableRandomization. --> |
| </dl> |
| <!-- man end --> |
| |
| <!-- man begin SEEALSO gdbserver --> |
| <!-- man end --> |
| </body></html> |
| |
