mingw/info/gdb/Invoking-GDB.html

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  12 Node:<a name="Invoking%20GDB">Invoking GDB</a>,
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  17
  18 <h3 class="section">Invoking GDB</h3>
  19
  20    <p>Invoke GDB by running the program <code>gdb</code>.  Once started,
  21 GDB reads commands from the terminal until you tell it to exit.
  22
  23    <p>You can also run <code>gdb</code> with a variety of arguments and options,
  24 to specify more of your debugging environment at the outset.
  25
  26    <p>The command-line options described here are designed
  27 to cover a variety of situations; in some environments, some of these
  28 options may effectively be unavailable.
  29
  30    <p>The most usual way to start GDB is with one argument,
  31 specifying an executable program:
  32
  33 <pre class="example">     gdb <var>program</var>
  34      </pre>
  35
  36 <p>You can also start with both an executable program and a core file
  37 specified:
  38
  39 <pre class="example">     gdb <var>program</var> <var>core</var>
  40      </pre>
  41
  42    <p>You can, instead, specify a process ID as a second argument, if you want
  43 to debug a running process:
  44
  45 <pre class="example">     gdb <var>program</var> 1234
  46      </pre>
  47
  48 <p>would attach GDB to process <code>1234</code> (unless you also have a file
  49 named <code>1234</code>; GDB does check for a core file first).
  50
  51    <p>Taking advantage of the second command-line argument requires a fairly
  52 complete operating system; when you use GDB as a remote
  53 debugger attached to a bare board, there may not be any notion of
  54 "process", and there is often no way to get a core dump.  GDB
  55 will warn you if it is unable to attach or to read core dumps.
  56
  57    <p>You can optionally have <code>gdb</code> pass any arguments after the
  58 executable file to the inferior using <code>--args</code>.  This option stops
  59 option processing.
  60 <pre class="example">     gdb --args gcc -O2 -c foo.c
  61      </pre>
  62    This will cause <code>gdb</code> to debug <code>gcc</code>, and to set
  63 <code>gcc</code>'s command-line arguments (see <a href="Arguments.html#Arguments">Arguments</a>) to <code>-O2 -c foo.c</code>.
  64
  65    <p>You can run <code>gdb</code> without printing the front material, which describes
  66 GDB's non-warranty, by specifying <code>-silent</code>:
  67
  68 <pre class="smallexample">     gdb -silent
  69      </pre>
  70
  71 <p>You can further control how GDB starts up by using command-line
  72 options.  GDB itself can remind you of the options available.
  73
  74 <p>Type
  75
  76 <pre class="example">     gdb -help
  77      </pre>
  78
  79 <p>to display all available options and briefly describe their use
  80 (<code>gdb -h</code> is a shorter equivalent).
  81
  82    <p>All options and command line arguments you give are processed
  83 in sequential order.  The order makes a difference when the
  84 <code>-x</code> option is used.
  85
  86 <ul class="menu">
  87 <li><a accesskey="1" href="File-Options.html#File%20Options">File Options</a>:                 Choosing files
  88 <li><a accesskey="2" href="Mode-Options.html#Mode%20Options">Mode Options</a>:                 Choosing modes
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