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diff --git a/lib/debugger/doc/src/debugger_chapter.xml b/lib/debugger/doc/src/debugger_chapter.xml index 98fe4ae377..45dfdb3776 100644 --- a/lib/debugger/doc/src/debugger_chapter.xml +++ b/lib/debugger/doc/src/debugger_chapter.xml @@ -4,7 +4,7 @@ <chapter> <header> <copyright> - <year>1997</year><year>2013</year> + <year>1997</year><year>2016</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -31,97 +31,92 @@ </header> <section> - <title>Introduction</title> + <title>Getting Started</title> - <p><em>Debugger</em> is a graphical user interface for the Erlang - interpreter, which can be used for debugging and testing of - Erlang programs. For example, breakpoints can be set, code can be - single stepped and variable values can be displayed and changed. - </p> + <p>To use Debugger, the basic steps are as follows:</p> - <p>The Erlang interpreter can also be accessed via the interface - module <c>int</c>, see <seealso marker="int">int(3)</seealso>. - </p> + <p><em>Step 1.</em> Start Debugger by calling + <c>debugger:start()</c>.</p> - <p><em>Warning:</em> Note that the Debugger at some point might - start tracing on the processes which execute the interpreted - code. This means that a conflict will occur if tracing by other - means is started on any of these processes.</p> - </section> + <p>The <seealso marker="#monitor">Monitor window</seealso> is + displayed with information about all debugged processes, + interpreted modules, and selected options. Initially there are + normally no debugged processes. First, it must be specified which + modules that are to be <em>debugged</em> (also called + <em>interpreted</em>). Proceed as follows:</p> - <section> - <title>Getting Started with Debugger</title> + <p><em>Step 2.</em> Select <em>Module > Interpret...</em> in the + Monitor window.</p> - <p>Start Debugger by calling <c>debugger:start()</c>. It will start - the <seealso marker="#monitor">Monitor window</seealso> showing - information about all debugged processes, interpreted modules and - selected options.</p> + <p>The <seealso marker="#interpret">Interpret Modules window</seealso> + is displayed.</p> - <p>Initially there are normally no debugged processes. First, it - must be specified which modules should be <em>debugged</em>, or - <em>interpreted</em> as it is also called. This is done by - choosing <em>Module->Interpret...</em> in the Monitor window and - then selecting the appropriate modules from the - <seealso marker="#interpret">Interpret Dialog window</seealso>. - </p> + <p><em>Step 3.</em> Select the appropriate modules from the Interpret + Dialog window.</p> <note> - <p>Only modules compiled with the option <c>debug_info</c> set - can be interpreted. Non-interpretable modules are shown within - parenthesis in the Interpret Dialog window.</p> + <p>Only modules compiled with option <c>debug_info</c> set can be + interpreted. Non-interpretable modules are displayed within + parenthesis in the Interpret Modules window.</p> </note> - <p>When a module is interpreted, it can be viewed in a - <seealso marker="#view">View Module window</seealso>. This is done - by selecting the module from the <em>Module->module->View</em> - menu. The contents of the source file is shown and it is possible - to set <seealso marker="#breakpoints">breakpoints</seealso>.</p> - - <p>Now the program that should be debugged can be started. This is - done the normal way from the Erlang shell. All processes executing - code in interpreted modules will be displayed in the Monitor - window. It is possible to <em>attach</em> to one of these - processes, by double-clicking it, or by selecting the process and - then choosing <em>Process->Attach</em>.</p> - - <p>Attaching to a process will result in a - <seealso marker="#attach">Attach Process window</seealso> being - opened for this process. From the Attach Process window, it is - possible to control the process execution, inspect variable - values, set breakpoints etc.</p> + <p><em>Step 4.</em> In the Monitor window, select + <em>Module > the module to be interpreted > View</em>.</p> + + <p>The contents of the source file is displayed in the + <seealso marker="#view">View Module window</seealso>.</p> + + <p><em>Step 5.</em> Set the + <seealso marker="#breakpoints">breakpoints</seealso>, if any.</p> + + <p><em>Step 6.</em> Start the program to be debugged. This is done + the normal way from the Erlang shell.</p> + + <p>All processes executing code in interpreted modules are displayed + in the Monitor window.</p> + + <p><em>Step 7.</em> To <em>attach</em> to one of these processes, + double-click it, or select the process and then choose + <em>Process > Attach</em>. Attaching to a process opens an + <seealso marker="#attach">Attach Process window</seealso> for this + process.</p> + + <p><em>Step 8.</em> From the Attach Process window, you can control + the process execution, inspect variable values, set breakpoints, + and so on.</p> </section> <section> <marker id="breakpoints"/> - <title>Breakpoints and Break Dialogue Windows</title> + <title>Breakpoints and Break Dialog Windows</title> <p>Once the appropriate modules are interpreted, breakpoints can be set at relevant locations in the source code. Breakpoints are specified on a line basis. When a process reaches a breakpoint, - it stops and waits for commands (step, skip, continue,...) from - the user.</p> + it stops and waits for commands (<em>Step</em>, <em>Skip</em>, + <em>Continue</em> ...) from the user.</p> <note> <p>When a process reaches a breakpoint, only that process is - stopped. Other processes are not affected.</p> + stopped. Other processes are not affected.</p> </note> - <p>Breakpoints are created and deleted using the Break menu of - the Monitor window, View Module window and Attach Process window. - </p> + <p>Breakpoints are created and deleted using the <em>Break</em> menu of + either the Monitor window, View Module window, or Attach Process + window.</p> <section> <title>Executable Lines</title> - <p>To have effect, a breakpoint must be set at an - <em>executable line</em>, which is a line of code containing an - executable expression such as a matching or a function call. - A blank line or a line containing a comment, function head or - pattern in a <c>case</c>- or <c>receive</c> statement is not - executable.</p> + <p>To have an effect, a breakpoint must be set at an + <em>executable line</em>, which is a line of code containing an + executable expression such as a matching or a function call. + A blank line or a line containing a comment, function head, or + pattern in a <c>case</c> statement or <c>receive</c> statement is not + executable.</p> - <p>In the example below, lines number 2, 4, 6, 8 and 11 are - executable lines:</p> + <p>In the following example, lines 2, 4, 6, 8, and 11 are + executable lines:</p> <pre> 1: is_loaded(Module,Compiled) -> 2: case get_file(Module,Compiled) of @@ -141,17 +136,15 @@ <title>Status and Trigger Action</title> <p>A breakpoint can be either <em>active</em> or - <em>inactive</em>. Inactive breakpoints are ignored.</p> - - <p>Each breakpoint has a <em>trigger action</em> which specifies - what should happen when a process has reached it (and stopped): - </p> - <list> - <item><em>enable</em> Breakpoint should remain active (default). - </item> - <item><em>disable</em> Breakpoint should be made inactive. - </item> - <item><em>delete</em> Breakpoint should be deleted.</item> + <em>inactive</em>. Inactive breakpoints are ignored.</p> + + <p>Each breakpoint has a <em>trigger action</em> that specifies + what is to happen when a process has reached it (and stopped):</p> + <list type="bulleted"> + <item><em>Enable</em> - Breakpoint is to remain active (default). + </item> + <item><em>Disable</em> - Breakpoint is to be made inactive.</item> + <item><em>Delete</em> - Breakpoint is to be deleted.</item> </list> </section> @@ -161,54 +154,56 @@ <p>A line breakpoint is created at a certain line in a module.</p> <image file="images/line_break_dialog.jpg"> - <icaption>The Line Break Dialog Window.</icaption> + <icaption>Line Break Dialog Window</icaption> </image> - <p>Right-clicking the Module entry will open a popup menu from - which the appropriate module can be selected.</p> + <p>Right-click the <em>Module</em> entry to open a popup menu from + which the appropriate module can be selected.</p> - <p>A line breakpoint can also be created (and deleted) by - double-clicking the line when the module is displayed in - the View Module or Attach Process window.</p> + <p>A line breakpoint can also be created (and deleted) by + double-clicking the line when the module is displayed in + the View Module window or Attach Process window.</p> </section> <section> <title>Conditional Breakpoints</title> <p>A conditional breakpoint is created at a certain line in - the module, but a process reaching the breakpoint will stop - only if a given condition is true.</p> + the module, but a process reaching the breakpoint stops + only if a specified condition is true.</p> <p>The condition is specified by the user as a module name - <c>CModule</c> and a function name <c>CFunction</c>. When a - process reaches the breakpoint, - <c>CModule:CFunction(Bindings)</c> will be evaluated. If and - only if this function call returns <c>true</c>, the process - will stop. If the function call returns <c>false</c>, - the breakpoint will be silently ignored.</p> - - <p><c>Bindings</c> is a list of variable bindings. Use - the function <c>int:get_binding(Variable,Bindings)</c> to - retrieve the value of <c>Variable</c> (given as an atom). - The function returns <c>unbound</c> or <c>{value,Value}</c>.</p> + <c>CModule</c> and a function name <c>CFunction</c>. When a + process reaches the breakpoint, + <c>CModule:CFunction(Bindings)</c> is evaluated. If and + only if this function call returns <c>true</c>, the process + stops. If the function call returns <c>false</c>, + the breakpoint is silently ignored.</p> + + <p><c>Bindings</c> is a list of variable bindings. To retrieve the + value of <c>Variable</c> (given as an atom), use function + <seealso marker="int#get_binding/2"><c>int:get_binding(Variable,Bindings)</c></seealso>. + The function returns <c>unbound</c> or <c>{value,Value}</c>.</p> <image file="images/cond_break_dialog.jpg"> - <icaption>The Conditional Break Dialog Window.</icaption> + <icaption>Conditional Break Dialog Window</icaption> </image> - <p>Right-clicking the Module entry will open a popup menu from - which the appropriate module can be selected.</p> + <p>Right-click the <em>Module</em> entry to open a popup menu from + which the appropriate module can be selected.</p> - <p>Example: A conditional breakpoint calling - <c>c_test:c_break/1</c> is added at line 6 in the module + <p><em>Example:</em></p> + + <p>A conditional breakpoint calling + <c>c_test:c_break/1</c> is added at line 6 in module <c>fact</c>. Each time the breakpoint is reached, the function is - called, and when <c>N</c> is equal to 3 it returns <c>true</c>, - and the process stops.</p> - + called. When <c>N</c> is equal to 3, the function returns + <c>true</c> and the process stops.</p> + <p>Extract from <c>fact.erl</c>:</p> <pre> -5. fac(0) -> 1; -6. fac(N) when N > 0, is_integer(N) -> N * fac(N-1).</pre> +5. fac(0) -> 1; +6. fac(N) when N > 0, is_integer(N) -> N * fac(N-1).</pre> <p>Definition of <c>c_test:c_break/1</c>:</p> <pre> @@ -228,18 +223,18 @@ c_break(Bindings) -> <title>Function Breakpoints</title> <p>A function breakpoint is a set of line breakpoints, one at - the first line of each clause in the given function.</p> + the first line of each clause in the specified function.</p> <image file="images/function_break_dialog.jpg"> - <icaption>The Function Break Dialog Window.</icaption> + <icaption>Function Break Dialog Window</icaption> </image> - <p>Right-clicking the Module entry will open a popup menu from - which the appropriate module can be selected.</p> + <p>To open a popup menu from which the appropriate module can be + selected, right-click the <em>Module</em> entry.</p> - <p>Clicking the Ok button (or 'Return' or 'Tab') when a module - name has been given, will bring up all functions of the module - in the listbox.</p> + <p>To bring up all functions of the module in the listbox, + click the <em>OK</em> button (or press the <em>Return</em> + or <em>Tab</em> key) when a module name has been specified,.</p> </section> </section> @@ -249,7 +244,7 @@ c_break(Bindings) -> <p>The Erlang emulator keeps track of a <em>stack trace</em>, information about recent function calls. This information is - used, for example, if an error occurs:</p> + used if an error occurs, for example:</p> <pre> 1> <input>catch a+1.</input> {'EXIT',{badarith,[{erlang,'+',[a,1],[]}, @@ -259,602 +254,597 @@ c_break(Bindings) -> {shell,eval_exprs,7,[{file,"shell.erl"},{line,629}]}, {shell,eval_loop,3,[{file,"shell.erl"},{line,614}]}]}}</pre> - <p>See the Erlang Reference Manual, - <seealso marker="doc/reference_manual:errors"> - Errors and Error Handling</seealso>, - for more information about the stack trace.</p> + <p>For details about the stack trace, see section + <seealso marker="doc/reference_manual:errors">Errors and Error Handling</seealso> + in the Erlang Reference Manual.</p> - <p>The Debugger emulates the stack trace by keeping track of recently + <p>Debugger emulates the stack trace by keeping track of recently called interpreted functions. (The real stack trace cannot be - used, as it shows which functions of the Debugger have been - called, rather than which interpreted functions).</p> + used, as it shows which functions of Debugger have been + called, rather than which interpreted functions.)</p> <p>This information can be used to traverse the chain of function - calls, using the 'Up' and 'Down' buttons of - <seealso marker="#attach">the Attach Process window</seealso>. - </p> + calls, using the <em>Up</em> and <em>Down</em> buttons in the + <seealso marker="#attach">Attach Process window</seealso>.</p> - <p>By default, the Debugger only saves information about recursive + <p>By default, Debugger only saves information about recursive function calls, that is, function calls that have not yet returned - a value (option 'Stack On, No Tail').</p> + a value (option <em>Stack On, No Tail</em>).</p> <p>Sometimes, however, it can be useful to save all calls, even - tail-recursive calls. That can be done with the 'Stack On, Tail' - option. Note that this option will consume more memory and slow - down execution of interpreted functions when there are many - tail-recursive calls. - </p> - - <p>It is also possible to turn off the Debugger stack trace - facility ('Stack Off'). <em>Note:</em> If an error occurs, in this - case the stack trace will be empty.</p> - - <p>See the section about <seealso marker="#monitor">the Monitor - Window</seealso> for information about how to change the stack - trace option.</p> + tail-recursive calls. This is done with option + <em>Stack On, Tail</em>. Notice that this option consumes more + memory and slows down execution of interpreted functions when there + are many tail-recursive calls.</p> + + <p>To turn off the Debugger stack trace facility, select option + <em>Stack Off</em>.</p> + + <note> + <p>If an error occurs, the stack trace becomes empty in this + case.</p> + </note> + + <p>For information about how to change the stack trace option, see + section <seealso marker="#monitor">Monitor Window</seealso>.</p> </section> <section> <marker id="monitor"/> - <title>The Monitor Window</title> + <title>Monitor Window</title> + + <p>The Monitor window is the main window of Debugger and displays the + following:</p> - <p>The Monitor window is the main window of Debugger and shows a - listbox containing the names of all interpreted modules - (double-clicking a module brings up the View Module window), - which options are selected, and information about all debugged - processes, that is all processes which have been/are executing - code in interpreted modules.</p> + <list type="bulleted"> + <item><p>A listbox containing the names of all interpreted + modules</p> + <p>Double-clicking a module brings up the View Module window.</p> + </item> + <item><p>Which options are selected</p></item> + <item><p>Information about all debugged processes, that is, all + processes that have been or are executing code in interpreted + modules</p></item> + </list> <image file="images/monitor.jpg"> - <icaption>The Monitor Window.</icaption> + <icaption>Monitor Window</icaption> </image> - <p>The Auto Attach buttons, Stack Trace label, Back Trace Size - label, and Strings button show some options set, see - <seealso marker="#options">Options Menu</seealso> for further - information about these options.</p> + <p>The <em>Auto Attach</em> boxes, <em>Stack Trace</em> label, + <em>Back Trace Size</em> label, and <em>Strings</em> box display + some options set. For details about these options, see section + <seealso marker="#options">Options Menu</seealso>.</p> <section> <title>Process Grid</title> - <taglist> <tag><em>Pid</em></tag> <item><p>The process identifier.</p></item> - + <tag><em>Initial Call</em></tag> <item><p>The first call to an interpreted function by this - process. (<c>Module:Function/Arity</c>)</p></item> + process. (<c>Module:Function/Arity</c>)</p></item> <tag><em>Name</em></tag> - <item><p>The registered name, if any. If a registered name does - not show up, it may be that the Debugger received - information about the process before the name had been - registered. Try selecting <em>Edit->Refresh</em>.</p></item> + <item><p>The registered name, if any. If a registered name is not + displayed, it can be that Debugger received information about + the process before the name was registered. Try selecting + <em>Edit > Refresh</em>.</p></item> <tag><em>Status</em></tag> <item><p>The current status, one of the following:</p> <taglist> <tag><em>idle</em></tag> - <item><p>The interpreted function call has returned a value, - and the process is no longer executing interpreted code. - </p></item> + <item><p>The interpreted function call has returned a value, and + the process is no longer executing interpreted code.</p></item> <tag><em>running</em></tag> <item><p>The process is running.</p></item> - + <tag><em>waiting</em></tag> <item><p>The process is waiting in a <c>receive</c> - statement.</p></item> - + statement.</p></item> + <tag><em>break</em></tag> <item><p>The process is stopped at a breakpoint.</p></item> - + <tag><em>exit</em></tag> <item><p>The process has terminated.</p></item> - + <tag><em>no_conn</em></tag> <item><p>There is no connection to the node where - the process is located.</p></item> + the process is located.</p></item> </taglist> </item> <tag><em>Information</em></tag> - <item><p>Additional information, if any. If the process is - stopped at a breakpoint, the field contains information - about the location <c>{Module,Line}</c>. If the process has - terminated, the field contains the exit reason.</p></item> + <item><p>More information, if any. If the process is + stopped at a breakpoint, the field contains information + about the location <c>{Module,Line}</c>. If the process has + terminated, the field contains the exit reason.</p></item> </taglist> </section> <section> - <title>The File Menu</title> - + <title>File Menu</title> + <taglist> <tag><em>Load Settings...</em></tag> - <item> - <p>Try to load and restore Debugger settings from a file - previously saved using <em>Save Settings...</em>, see below. - Any errors are silently ignored. - <em>Note:</em> Settings saved by Erlang R16B01 or later - cannot be read by Erlang R16B or earlier.</p> + <item><p>Tries to load and restore Debugger settings from a file + previously saved using <em>Save Settings...</em> (see below). + Any errors are silently ignored.</p> + <p>Notice that settings saved by Erlang/OTP R16B01 or later + cannot be read by Erlang/OTP R16B or earlier.</p> </item> - + <tag><em>Save Settings...</em></tag> - <item><p>Save Debugger settings to a file. The settings include - the set of interpreted files, breakpoints, and the selected - options. The settings can be restored in a later Debugger - session using <em>Load Settings...</em>, see above. - Any errors are silently ignored.</p> + <item><p>Saves Debugger settings to a file. The settings include + the set of interpreted files, breakpoints, and the selected + options. The settings can be restored in a later Debugger + session using <em>Load Settings...</em> (see above). + Any errors are silently ignored.</p> </item> - + <tag><em>Exit</em></tag> - <item><p>Stop Debugger.</p></item> + <item><p>Stops Debugger.</p></item> </taglist> </section> <section> - <title>The Edit Menu</title> + <title>Edit Menu</title> <taglist> <tag><em>Refresh</em></tag> - <item><p>Update information about debugged processes. Removes - information about all terminated processes from the window, - and also closes all Attach Process windows for terminated - processes.</p></item> + <item><p>Updates information about debugged processes. Information + about all terminated processes are removed from the window. All + Attach Process windows for terminated processes are closed.</p></item> <tag><em>Kill All</em></tag> - <item><p>Terminate all processes listed in the window using - <c>exit(Pid,kill)</c>.</p></item> + <item><p>Terminates all processes listed in the window using + <c>exit(Pid,kill)</c>.</p></item> </taglist> </section> <section> - <title>The Module Menu</title> + <title>Module Menu</title> <taglist> <tag><em>Interpret...</em></tag> - <item><p>Open the <seealso marker="#interpret">Interpret Dialog - window</seealso> where new modules to be interpreted can - be specified.</p></item> - + <item><p>Opens the + <seealso marker="#interpret">Interpret Modules window</seealso>, + where new modules to be interpreted can be specified.</p></item> + <tag><em>Delete All</em></tag> - <item><p>Stop interpreting all modules. Processes executing in - interpreted modules will terminate.</p></item> + <item><p>Stops interpreting all modules. Processes executing in + interpreted modules terminate.</p></item> </taglist> <p>For each interpreted module, a corresponding entry is added to - the Module menu, with the following submenu:</p> + the <em>Module</em> menu, with the following submenu:</p> <taglist> <tag><em>Delete</em></tag> - <item><p>Stop interpreting the selected module. Processes - executing in this module will terminate.</p></item> - + <item><p>Stops interpreting the selected module. Processes + executing in this module terminate.</p></item> + <tag><em>View</em></tag> - <item><p>Open a <seealso marker="#view">View Module - window</seealso> showing the contents of the selected - module.</p></item> + <item><p>Opens a + <seealso marker="#view">View Module window</seealso>, displaying the + contents of the selected module.</p></item> </taglist> </section> <section> - <title>The Process Menu</title> + <title>Process Menu</title> <p>The following menu items apply to the currently selected - process, provided it is stopped at a breakpoint. See the chapter - about the <seealso marker="#attach">Attach Process - window</seealso> for more information.</p> + process, provided it is stopped at a breakpoint (for details, see + section + <seealso marker="#attach">Attach Process window</seealso>):</p> <taglist> <tag><em>Step</em></tag><item></item> <tag><em>Next</em></tag><item></item> <tag><em>Continue</em></tag><item></item> <tag><em>Finish</em></tag><item></item> </taglist> + <p>The following menu items apply to the currently selected - process.</p> + process:</p> <taglist> <tag><em>Attach</em></tag> - <item><p>Attach to the process and open a - <seealso marker="#attach">Attach Process window</seealso>. - </p></item> - + <item><p>Attaches to the process and open an + <seealso marker="#attach">Attach Process window</seealso>.</p></item> + <tag><em>Kill</em></tag> - <item><p>Terminate the process using <c>exit(Pid,kill)</c>.</p> - </item> + <item><p>Terminates the process using <c>exit(Pid,kill)</c>.</p></item> </taglist> </section> - <section> - <title>The Break Menu</title> - <p>The items in this menu are used to create and delete - breakpoints. - See the <seealso marker="#breakpoints">Breakpoints</seealso> - chapter for more information.</p> + <section> + <title>Break Menu</title> + <p>The items in this menu are used to create and delete breakpoints. + For details, see section + <seealso marker="#breakpoints">Breakpoints</seealso>.</p> + <taglist> <tag><em>Line Break...</em></tag> - <item><p>Set a line breakpoint.</p></item> + <item><p>Sets a line breakpoint.</p></item> <tag><em>Conditional Break...</em></tag> - <item><p>Set a conditional breakpoint.</p></item> + <item><p>Sets a conditional breakpoint.</p></item> <tag><em>Function Break...</em></tag> - <item><p>Set a function breakpoint.</p></item> + <item><p>Sets a function breakpoint.</p></item> <tag><em>Enable All</em></tag> - <item><p>Enable all breakpoints.</p></item> + <item><p>Enables all breakpoints.</p></item> <tag><em>Disable All</em></tag> - <item><p>Disable all breakpoints.</p></item> + <item><p>Disables all breakpoints.</p></item> - <tag><em>Delete All</em></tag> - <item><p>Remove all breakpoints.</p></item> + <tag><em>Delete All</em></tag> + <item><p>Removes all breakpoints.</p></item> </taglist> - <p>For each breakpoint, a corresponding entry is added to - the Break - menu, from which it is possible to disable/enable or delete - the breakpoint, and to change its trigger action.</p> + <p>For each breakpoint, a corresponding entry is added to the + <em>Break</em> menu, from which it is possible to disable, enable, + or delete the breakpoint, and to change its trigger action.</p> </section> <section> <marker id="options"/> - <title>The Options Menu</title> + <title>Options Menu</title> <taglist> <tag><em>Trace Window</em></tag> - <item><p>Set which areas should be visible in - an <seealso marker="#attach">Attach Process - window</seealso>. Does not affect already existing - Attach Process windows.</p> + <item><p>Sets the areas to be visible in an + <seealso marker="#attach">Attach Process window</seealso>. + Does not affect existing Attach Process windows.</p> </item> <tag><em>Auto Attach</em></tag> - <item><p>Set at which events a debugged process should be - automatically attached to. Affects existing debugged - processes.</p> - <list> - <item><em>First Call</em> - the first time a process calls a - function in an interpreted module.</item> - <item><em>On Exit</em> - at process termination.</item> - <item><em>On Break</em> - when a process reaches a - breakpoint.</item> + <item><p>Sets the events a debugged process is to be attached + to automatically. Affects existing debugged processes.</p> + <list type="bulleted"> + <item><p><em>First Call</em> - The first time a process calls + a function in an interpreted module.</p></item> + <item><p><em>On Exit</em> - At process termination.</p></item> + <item><p><em>On Break</em> - When a process reaches a + breakpoint.</p></item> </list> </item> <tag><em>Stack Trace</em></tag> - <item><p>Set stack trace option, see section + <item><p>Sets the stack trace option, see section <seealso marker="#stack_trace">Stack Trace</seealso>. Does not - affect already existing debugged processes.</p> - <list> - <item><em>Stack On, Tail</em> - save information about all - current calls.</item> - <item><em>Stack On, No Tail</em> - save information about + affect existing debugged processes.</p> + <list type="bulleted"> + <item><p><em>Stack On, Tail</em> - Saves information about all + current calls.</p></item> + <item><p><em>Stack On, No Tail</em> - Saves information about current calls, discarding previous information when a tail - recursive call is made.</item> - <item><em>Stack Off</em> - do not save any information about - current calls.</item> + recursive call is made.</p></item> + <item><p><em>Stack Off</em> - Does not save any information about + current calls.</p></item> </list> </item> <tag><em>Strings</em></tag> - <item><p>Set which integer lists should be printed as strings. - Does not affect already existing debugged processes.</p> - <list> - - <item><em>Use range of +pc flag</em> - use the printable - character range set by the - <seealso marker="erts:erl#printable_character_range"> - <c>erl(1)</c></seealso> flag <c>+pc</c>. - </item> + <item><p>Sets the integer lists to be printed as strings. + Does not affect existing debugged processes.</p> + <list type="bulleted"> + <item><p><em>Use range of +pc flag</em> - Uses the printable + character range set by the <c>erl(1)</c> flag + <seealso marker="erts:erl#printable_character_range"><c>+pc</c></seealso>.</p> + </item> </list> </item> <tag><em>Back Trace Size...</em></tag> - <item><p>Set how many call frames should be fetched when - inspecting the call stack from the Attach Process window. - Does not affect already existing Attach Process windows.</p> + <item><p>Sets how many call frames to be fetched when + inspecting the call stack from the Attach Process window. + Does not affect existing Attach Process windows.</p> </item> </taglist> </section> <section> - <title>The Windows Menu</title> + <title>Windows Menu</title> <p>Contains a menu item for each open Debugger window. Selecting - one of the items will raise the corresponding window.</p> + one of the items raises the corresponding window.</p> </section> <section> - <title>The Help Menu</title> + <title>Help Menu</title> <taglist> <tag><em>Help</em></tag> - <item><p>View the Debugger documentation. Currently this - function requires a web browser to be up and running.</p></item> + <item><p>Shows the Debugger documentation. This function requires a + web browser.</p></item> </taglist> </section> </section> - + <section> <marker id="interpret"/> - <title>The Interpret Dialog Window</title> + <title>Interpret Modules Window</title> - <p>The interpret dialog module is used for selecting which modules - to interpret. Initially, the window shows the modules (<c>erl</c> - files) and subdirectories of the current working directory.</p> + <p>The Interpret Modules window is used for selecting which modules + to interpret. Initially, the window displays the modules (<c>erl</c> + files) and subdirectories of the current working directory.</p> - <p>Interpretable modules are modules for which a BEAM file, compiled - with the option <c>debug_info</c> set, can be found in the same + <p>Interpretable modules are modules for which a <c>.beam</c> file, + compiled with option <c>debug_info</c> set, is located in the same directory as the source code, or in an <c>ebin</c> directory next to it.</p> - <p>Modules, for which the above requirements are not fulfilled, are - not interpretable and are therefore displayed within parentheses. - </p> + <p>Modules for which these requirements are not fulfilled are + not interpretable and are therefore displayed within parentheses.</p> - <p>The <c>debug_info</c> option causes <em>debug information</em> or - <em>abstract code</em> to be added to the BEAM file. This will - increase the size of the file, and also makes it possible to + <p>Option <c>debug_info</c> causes <em>debug information</em> or + <em>abstract code</em> to be added to the <c>.beam</c> file. + This increases the file size and makes it possible to reconstruct the source code. It is therefore recommended not to include debug information in code aimed for target systems.</p> <p>An example of how to compile code with debug information using - <c>erlc</c>:<br/> - <c>% erlc +debug_info module.erl</c></p> - + <c>erlc</c>:</p> + <pre> +% erlc +debug_info module.erl</pre> + <p>An example of how to compile code with debug information from - the Erlang shell:<br/> - <c>4> c(module, debug_info).</c></p> - + the Erlang shell:</p> + <pre> +4> c(module, debug_info).</pre> + <image file="images/interpret.jpg"> - <icaption>The Interpret Dialog Window.</icaption> + <icaption>Interpret Modules Window</icaption> </image> - <p>Browse the file hierarchy and interpret the appropriate modules - by selecting a module name and pressing <em>Choose</em> (or - carriage return), or by double clicking the module name. - Interpreted modules have the type <c>erl src</c>. - </p> + <p>To browse the file hierarchy and interpret the appropriate modules, + either select a module name and click <em>Choose</em> (or + press carriage return), or double-click the module name. + Interpreted modules have the type <c>erl src</c>.</p> - <p>Pressing <em>All</em> will interpret all displayed modules in - the chosen directory.</p> + <p>To interpret all displayed modules in the chosen directory, click + <em>All</em>.</p> - <p>Pressing <em>Done</em> will close the window.</p> + <p>To close the window, click <em>Done</em>.</p> <note> - <p>When the Debugger is started in global mode (which is - the default, see - <seealso marker="debugger:debugger#start/0">debugger:start/0</seealso>), - modules added (or deleted) for interpretation will be added (or - deleted) on all known Erlang nodes.</p> + <p>When Debugger is started in global mode (which is the default, see + <seealso marker="debugger#start/0">debugger:start/0</seealso>), + modules added (or deleted) for interpretation are added (or + deleted) on all known Erlang nodes.</p> </note> </section> <section> <marker id="attach"/> - <title>The Attach Process Window</title> + <title>Attach Process Window</title> - <p>From an Attach Process window the user can interact with a + <p>From an Attach Process window, you can interact with a debugged process. One window is opened for each process that has - been attached to. Note that when attaching to a process, its - execution is automatically stopped. - </p> + been attached to. Notice that when attaching to a process, its + execution is automatically stopped.</p> <image file="images/attach.jpg"> - <icaption>The Attach Process Window.</icaption> + <icaption>Attach Process Window</icaption> </image> - <p>The window is divided into five parts:</p> - <list> - <item><p>The Code area, showing the code being executed. The code - is indented and each line is prefixed with its line number. - If the process execution is stopped, the current line is - marked with <em>--></em>. An existing break point at a line - is marked with a stop symbol. In the example above, - the execution has been stopped at line 6, before - the execution of <c>fac/1</c>.</p> - <p>Active breakpoints are shown in red, while inactive - breakpoints are shown in blue.</p> + <p>The window is divided into the following five parts:</p> + <list type="bulleted"> + <item><p>The Code area, displaying the code being executed. The code + is indented and each line is prefixed with its line number. + If the process execution is stopped, the current line is + marked with <c>--></c>. An existing break point at a line + is marked with a stop symbol. In the example shown in the + illustration, the execution stopped at line 6, before + the execution of <c>fac/1</c>.</p> + + <p>Active breakpoints are displayed in red and inactive + breakpoints in blue.</p> </item> - <item>The Button area, with buttons for quick access to frequently - used functions in the Process menu.</item> - <item>The Evaluator area, where the user can evaluate functions - within the context of the debugged process, provided that - process execution has been stopped.</item> - <item>The Bindings area, showing all variables bindings. - Clicking on a variable name will result in the value being - displayed in the Evaluator area. - Double-clicking on a variable name will open a window where - the variable value may be edited. Note however that pid, - reference, binary or port values can not be edited. + + <item><p>The Button area, with buttons for quick access to frequently + used functions in the <em>Process</em> menu.</p></item> + + <item><p>The Evaluator area, where you can evaluate functions + within the context of the debugged process, if that + process execution is stopped.</p></item> + + <item><p>The Bindings area, displaying all variables bindings. If you + click a variable name, the value is displayed in the Evaluator area. + Double-click a variable name to open a window where + the variable value can be edited. Notice however that pid, + reference, binary, or port values cannot be edited.</p> </item> - <item><p>The Trace area, showing a trace output for the process. - </p> + + <item><p>The Trace area, which displays a trace output for the + process.</p> <taglist> - <tag><c>++ (N) <L></c></tag> - <item>Function call, where <c>N</c> is the call level and - <c>L</c> the line number.</item> + <tag><c>++ (N) <L></c></tag> + <item><p>Function call, where <c>N</c> is the call level and + <c>L</c> the line number.</p></item> - <tag><c>-- (N)</c></tag> - <item>Function return value.</item> + <tag><c>-- (N)</c></tag> + <item><p>Function return value</p>.</item> - <tag><c>==> Pid : Msg</c></tag> - <item>The message <c>Msg</c> is sent to process <c>Pid</c>. - </item> + <tag><c>==> Pid : Msg</c></tag> + <item><p>The message <c>Msg</c> is sent to process + <c>Pid</c>.</p></item> - <tag><c><![CDATA[<== Msg]]></c></tag> - <item>The message <c>Msg</c> is received.</item> + <tag><c><![CDATA[<== Msg]]></c></tag> + <item><p>The message <c>Msg</c> is received.</p></item> - <tag><c>++ (N) receive</c></tag> - <item>Waiting in a <c>receive</c>.</item> + <tag><c>++ (N) receive</c></tag> + <item><p>Waiting in a <c>receive</c>.</p></item> - <tag><c>++ (N) receive with timeout</c></tag> - <item>Waiting in a <c>receive...after</c>.</item> - </taglist> + <tag><c>++ (N) receive with timeout</c></tag> + <item><p>Waiting in a <c>receive...after</c>.</p></item> + </taglist> - <p>Also the back trace, a summary of the current function calls - on the stack, is displayed in the Trace area.</p> + <p>The Trace area also displays Back Trace, a summary of the + current function calls on the stack.</p> </item> </list> - <p>It is configurable using the Options menu which areas should - be shown or hidden. By default, all areas except the Trace area - are shown.</p> + <p>Using the <em>Options</em> menu, you can set which areas to be + displayed. By default, all areas except the Trace area are displayed.</p> <section> - <title>The File Menu</title> + <title>File Menu</title> <taglist> <tag><em>Close</em></tag> - <item><p>Close this window and detach from the process.</p> + <item><p>Closes this window and detach from the process.</p> </item> </taglist> </section> <section> - <title>The Edit Menu</title> + <title>Edit Menu</title> <taglist> <tag><em>Go to line...</em></tag> - <item><p>Go to a specified line number.</p></item> + <item><p>Goes to a specified line number.</p></item> <tag><em>Search...</em></tag> - <item><p>Search for a specified string.</p></item> + <item><p>Searches for a specified string.</p></item> </taglist> </section> <section> - <title>The Process Menu</title> + <title>Process Menu</title> <taglist> <tag><em>Step</em></tag> - <item><p>Execute the current line of code, stepping into any + <item><p>Executes the current code line, stepping into any (interpreted) function calls.</p></item> <tag><em>Next</em></tag> - <item><p>Execute the current line of code and stop at the next + <item><p>Executes the current code line and stop at the next line.</p></item> <tag><em>Continue</em></tag> - <item><p>Continue the execution.</p></item> + <item><p>Continues the execution.</p></item> <tag><em>Finish</em></tag> - <item><p>Continue the execution until the current function + <item><p>Continues the execution until the current function returns.</p></item> <tag><em>Skip</em></tag> - <item><p>Skip the current line of code and stop at the next + <item><p>Skips the current code line and stop at the next line. If used on the last line in a function body, - the function will return <c>skipped</c>.</p></item> + the function returns <c>skipped</c>.</p></item> <tag><em>Time Out</em></tag> - <item><p>Simulate a timeout when executing a + <item><p>Simulates a time-out when executing a <c>receive...after</c> statement.</p></item> <tag><em>Stop</em></tag> - <item><p>Stop the execution of a running process, that is, make - the process stop as at a breakpoint. The command will take + <item><p>Stops the execution of a running process, that is, make + the process stop at a breakpoint. The command takes effect (visibly) the next time the process receives a message.</p></item> <tag><em>Where</em></tag> - <item><p>Make sure the current location of the execution is + <item><p>Verifies that the current location of the execution is visible in the code area.</p></item> <tag><em>Kill</em></tag> - <item><p>Terminate the process using <c>exit(Pid,kill)</c>.</p> + <item><p>Terminates the process using <c>exit(Pid,kill)</c>.</p> </item> <tag><em>Messages</em></tag> - <item><p>Inspect the message queue of the process. The queue is - printed in the evaluator area.</p></item> + <item><p>Inspects the message queue of the process. The queue is + displayed in the Evaluator area.</p></item> <tag><em>Back Trace</em></tag> - <item><p>Display the back trace of the process, a summary of - the current function calls on the stack, in the trace area. - Requires that the Trace area is visible and that the stack - trace option is 'Stack On, Tail' or 'Stack On, No Tail'.</p> + <item><p>Displays the back trace of the process, a summary of + the current function calls on the stack, in the Trace area. + Requires that the Trace area is visible and that the Stack + Trace option is <em>Stack On, Tail</em> or + <em>Stack On, No Tail</em>.</p> </item> <tag><em>Up</em></tag> - <item><p>Inspect the previous function call on the stack, + <item><p>Inspects the previous function call on the stack, showing the location and variable bindings.</p></item> <tag><em>Down</em></tag> - <item><p>Inspect the next function call on the stack, showing + <item><p>Inspects the next function call on the stack, showing the location and variable bindings.</p></item> </taglist> </section> <section> - <title>The Options Menu</title> + <title>Options Menu</title> <taglist> <tag><em>Trace Window</em></tag> - <item><p>Set which areas should be visible. Does not affect - other Attach Process windows.</p> - </item> + <item><p>Sets which areas are to be visible. Does not affect + other Attach Process windows.</p></item> <tag><em>Stack Trace</em></tag> - <item><p>Same as in <seealso marker="#monitor">the Monitor - window</seealso>, but only affects the debugged - process the window is attached to.</p> - </item> + <item><p>Same as in the <seealso marker="#monitor">Monitor + window</seealso>, but only affects the debugged + process the window is attached to.</p></item> <tag><em>Strings</em></tag> - <item><p>Same as in <seealso marker="#monitor">the Monitor - window</seealso>, but only affects the debugged - process the window is attached to.</p> - </item> + <item><p>Same as in the <seealso marker="#monitor">Monitor + window</seealso>, but only affects the debugged + process the window is attached to.</p></item> <tag><em>Back Trace Size...</em></tag> - <item><p>Set how many call frames should be fetched when + <item><p>Sets how many call frames are to be fetched when inspecting the call stack. Does not affect other Attach - Process windows.</p> - </item> + Process windows.</p></item> </taglist> </section> <section> - <title>Break, Windows and Help Menus</title> + <title>Break, Windows, and Help Menus</title> - <p>The Break, Windows and Help menus look the same as in - the Monitor window, see the chapter - <seealso marker="#monitor">The Monitor Window</seealso>, except - that the Breaks menu apply to the local breakpoints only.</p> + <p>The <em>Break</em>, <em>Windows</em>, and <em>Help</em> menus + are the same as in the + <seealso marker="#monitor">Monitor Window</seealso>, except + that the <em>Breaks</em> menu applies only to local + breakpoints.</p> </section> </section> <section> <marker id="view"/> - <title>The View Module Window</title> + <title>View Module Window</title> - <p>The View Module window shows the contents of an interpreted + <p>The View Module window displays the contents of an interpreted module and makes it possible to set breakpoints.</p> <image file="images/view.jpg"> - <icaption>The View Module Window.</icaption> + <icaption>View Module Window</icaption> </image> <p>The source code is indented and each line is prefixed with its line number.</p> - <p>Clicking a line will highlight it and select it to be the target - of the breakpoint functions available from the Break menu. - Doubleclicking a line will set a line breakpoint on that line. - Doubleclicking a line with an existing breakpoint will remove - the breakpoint.</p> + <p>Clicking a line highlights it and selects it to be the target + of the breakpoint functions available from the <em>Break</em> menu. + To set a line breakpoint on a line, double-click it. + To remove the breakpoint, double-click the line with an existing + breakpoint.</p> <p>Breakpoints are marked with a stop symbol.</p> <section> <title>File and Edit Menus</title> - <p>The File and Edit menus look the same as in the Attach Process - window, see the chapter <seealso marker="#attach">The Attach - Process Window</seealso>.</p> + <p>The <em>File</em> and <em>Edit</em> menus are the same as in the + <seealso marker="#attach">Attach Process Window</seealso>.</p> </section> <section> - <title>Break, Windows and Help Menus</title> + <title>Break, Windows, and Help Menus</title> - <p>The Break, Windows and Help menus look the same as in - the Monitor window, see the chapter - <seealso marker="#monitor">The Monitor Window</seealso>, except - that the Breaks menu apply to the local breakpoints only.</p> + <p>The <em>Break</em>, <em>Windows</em>, and <em>Help</em> menus + are the same as in the + <seealso marker="#monitor">Monitor Window</seealso>, except + that the <em>Break</em> menu applies only to local breakpoints.</p> </section> </section> @@ -862,14 +852,14 @@ c_break(Bindings) -> <title>Performance</title> <p>Execution of interpreted code is naturally slower than for - regularly compiled modules. Using the Debugger also increases + regularly compiled modules. Using Debugger also increases the number of processes in the system, as for each debugged process another process (the meta process) is created.</p> - <p>It is also worth to keep in mind that programs with timers may + <p>It is also worth to keep in mind that programs with timers can behave differently when debugged. This is especially true when - stopping the execution of a process, for example at a - breakpoint. Timeouts can then occur in other processes that + stopping the execution of a process (for example, at a + breakpoint). Time-outs can then occur in other processes that continue execution as normal.</p> </section> @@ -878,8 +868,8 @@ c_break(Bindings) -> <p>Code loading works almost as usual, except that interpreted modules are also stored in a database and debugged processes - uses only this stored code. Re-interpreting an interpreted - module will result in the new version being stored as well, but + use only this stored code. Reinterpreting an interpreted + module results in the new version being stored as well, but does not affect existing processes executing an older version of the code. This means that the code replacement mechanism of Erlang does not work for debugged processes.</p> @@ -888,22 +878,24 @@ c_break(Bindings) -> <section> <title>Debugging Remote Nodes</title> - <p>By using <c>debugger:start/1</c>, it can be specified if Debugger - should be started in local or global mode.</p> + <p>By using + <seealso marker="debugger#start/1">debugger:start/1</seealso>, + you can specify if Debugger is to be started in local or global + mode:</p> <pre> debugger:start(local | global)</pre> - <p>If no argument is provided, Debugger is started in global mode. - </p> + + <p>If no argument is provided, Debugger starts in global mode.</p> <p>In local mode, code is interpreted only at the current node. In global mode, code is interpreted at all known nodes. Processes - at other nodes executing interpreted code will automatically be - shown in the Monitor window and can be attached to like any other + at other nodes executing interpreted code are automatically + displayed in the Monitor window and can be attached to like any other debugged process.</p> - <p>It is possible, but definitely not recommended to start Debugger - in global mode on more than one node in a network, as they will - interfere with each other leading to inconsistent behaviour.</p> + <p>It is possible, but definitely not recommended, to start Debugger + in global mode on more than one node in a network, as the nodes + interfere with each other, leading to inconsistent behavior.</p> </section> </chapter> |