\input texinfo @c -*-texinfo-*-
-@c Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998,
-@c 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
-@c Free Software Foundation, Inc.
+@c Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996,
+@c 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
+@c 2010, 2011 Free Software Foundation, Inc.
@c
@c %**start of header
@c makeinfo ignores cmds prev to setfilename, so its arg cannot make use
* GDB Bugs:: Reporting bugs in @value{GDBN}
+@ifset SYSTEM_READLINE
+* Command Line Editing: (rluserman). Command Line Editing
+* Using History Interactively: (history). Using History Interactively
+@end ifset
+@ifclear SYSTEM_READLINE
* Command Line Editing:: Command Line Editing
* Using History Interactively:: Using History Interactively
+@end ifclear
* Formatting Documentation:: How to format and print @value{GDBN} documentation
* Installing GDB:: Installing GDB
* Maintenance Commands:: Maintenance Commands
Support for Modula-2 is partial. For information on Modula-2, see
@ref{Modula-2,,Modula-2}.
+Support for OpenCL C is partial. For information on OpenCL C, see
+@ref{OpenCL C,,OpenCL C}.
+
@cindex Pascal
Debugging Pascal programs which use sets, subranges, file variables, or
nested functions does not currently work. @value{GDBN} does not support
command files specified with @samp{-x} (and all commands from
initialization files, if not inhibited with @samp{-n}). Exit with
nonzero status if an error occurs in executing the @value{GDBN} commands
-in the command files. Batch mode also disables pagination;
-@pxref{Screen Size} and acts as if @kbd{set confirm off} were in
-effect (@pxref{Messages/Warnings}).
+in the command files. Batch mode also disables pagination, sets unlimited
+terminal width and height @pxref{Screen Size}, and acts as if @kbd{set confirm
+off} were in effect (@pxref{Messages/Warnings}).
Batch mode may be useful for running @value{GDBN} as a filter, for
example to download and run a program on another computer; in order to
Run @value{GDBN} using @var{directory} as its working directory,
instead of the current directory.
+@item -data-directory @var{directory}
+@cindex @code{--data-directory}
+Run @value{GDBN} using @var{directory} as its data directory.
+The data directory is where @value{GDBN} searches for its
+auxiliary files. @xref{Data Files}.
+
@item -fullname
@itemx -f
@cindex @code{--fullname}
to the program you are debugging, in the directory where you invoke
@value{GDBN}.
+@item
+If the command line specified a program to debug, or a process to
+attach to, or a core file, @value{GDBN} loads any auto-loaded
+scripts provided for the program or for its loaded shared libraries.
+@xref{Auto-loading}.
+
+If you wish to disable the auto-loading during startup,
+you must do something like the following:
+
+@smallexample
+$ gdb -ex "set auto-load-scripts off" -ex "file myprogram"
+@end smallexample
+
+The following does not work because the auto-loading is turned off too late:
+
+@smallexample
+$ gdb -ex "set auto-load-scripts off" myprogram
+@end smallexample
+
@item
Reads command files specified by the @samp{-x} option. @xref{Command
Files}, for more details about @value{GDBN} command files.
@kindex detach inferior @var{infno}
@item detach inferior @var{infno}
Detach from the inferior identified by @value{GDBN} inferior number
-@var{infno}, and remove it from the inferior list.
+@var{infno}. Note that the inferior's entry still stays on the list
+of inferiors shown by @code{info inferiors}, but its Description will
+show @samp{<null>}.
@kindex kill inferior @var{infno}
@item kill inferior @var{infno}
Kill the inferior identified by @value{GDBN} inferior number
-@var{infno}, and remove it from the inferior list.
+@var{infno}. Note that the inferior's entry still stays on the list
+of inferiors shown by @code{info inferiors}, but its Description will
+show @samp{<null>}.
@end table
After the successful completion of a command such as @code{detach},
@kindex show libthread-db-search-path
@item show libthread-db-search-path
Display current libthread_db search path.
+
+@kindex set debug libthread-db
+@kindex show debug libthread-db
+@cindex debugging @code{libthread_db}
+@item set debug libthread-db
+@itemx show debug libthread-db
+Turns on or off display of @code{libthread_db}-related events.
+Use @code{1} to enable, @code{0} to disable.
@end table
@node Forks
@table @code
@kindex watch
-@item watch @var{expr} @r{[}thread @var{threadnum}@r{]}
+@item watch @r{[}-l@r{|}-location@r{]} @var{expr} @r{[}thread @var{threadnum}@r{]}
Set a watchpoint for an expression. @value{GDBN} will break when the
expression @var{expr} is written into by the program and its value
changes. The simplest (and the most popular) use of this command is
that watchpoints restricted to a single thread in this way only work
with Hardware Watchpoints.
+Ordinarily a watchpoint respects the scope of variables in @var{expr}
+(see below). The @code{-location} argument tells @value{GDBN} to
+instead watch the memory referred to by @var{expr}. In this case,
+@value{GDBN} will evaluate @var{expr}, take the address of the result,
+and watch the memory at that address. The type of the result is used
+to determine the size of the watched memory. If the expression's
+result does not have an address, then @value{GDBN} will print an
+error.
+
@kindex rwatch
-@item rwatch @var{expr} @r{[}thread @var{threadnum}@r{]}
+@item rwatch @r{[}-l@r{|}-location@r{]} @var{expr} @r{[}thread @var{threadnum}@r{]}
Set a watchpoint that will break when the value of @var{expr} is read
by the program.
@kindex awatch
-@item awatch @var{expr} @r{[}thread @var{threadnum}@r{]}
+@item awatch @r{[}-l@r{|}-location@r{]} @var{expr} @r{[}thread @var{threadnum}@r{]}
Set a watchpoint that will break when @var{expr} is either read from
or written into by the program.
@c RET-repeat for @code{directory} is explicitly disabled, but since
@c repeating it would be a no-op we do not say that. (thanks to RMS)
+@item set directories @var{path-list}
+@kindex set directories
+Set the source path to @var{path-list}.
+@samp{$cdir:$cwd} are added if missing.
+
@item show directories
@kindex show directories
Print the source path: show which directories it contains.
command is a program counter value; @value{GDBN} dumps the function
surrounding this value. When two arguments are given, they should
be separated by a comma, possibly surrounded by whitespace. The
-arguments specify a range of addresses (first inclusive, second exclusive)
-to dump. In that case, the name of the function is also printed (since
-there could be several functions in the given range).
+arguments specify a range of addresses to dump, in one of two forms:
+
+@table @code
+@item @var{start},@var{end}
+the addresses from @var{start} (inclusive) to @var{end} (exclusive)
+@item @var{start},+@var{length}
+the addresses from @var{start} (inclusive) to
+@code{@var{start}+@var{length}} (exclusive).
+@end table
+
+@noindent
+When 2 arguments are specified, the name of the function is also
+printed (since there could be several functions in the given range).
The argument(s) can be any expression yielding a numeric value, such as
@samp{0x32c4}, @samp{&main+10} or @samp{$pc - 8}.
End of assembler dump.
@end smallexample
+Here is another example showing raw instructions in hex for AMD x86-64,
+
+@smallexample
+(gdb) disas /r 0x400281,+10
+Dump of assembler code from 0x400281 to 0x40028b:
+ 0x0000000000400281: 38 36 cmp %dh,(%rsi)
+ 0x0000000000400283: 2d 36 34 2e 73 sub $0x732e3436,%eax
+ 0x0000000000400288: 6f outsl %ds:(%rsi),(%dx)
+ 0x0000000000400289: 2e 32 00 xor %cs:(%rax),%al
+End of assembler dump.
+@end smallexample
+
Some architectures have more than one commonly-used set of instruction
mnemonics or other syntax.
Python code. It greatly simplifies the display of complex objects. This
mechanism works for both MI and the CLI.
-For example, here is how a C@t{++} @code{std::string} looks without a
-pretty-printer:
+@menu
+* Pretty-Printer Introduction:: Introduction to pretty-printers
+* Pretty-Printer Example:: An example pretty-printer
+* Pretty-Printer Commands:: Pretty-printer commands
+@end menu
+
+@node Pretty-Printer Introduction
+@subsection Pretty-Printer Introduction
+
+When @value{GDBN} prints a value, it first sees if there is a pretty-printer
+registered for the value. If there is then @value{GDBN} invokes the
+pretty-printer to print the value. Otherwise the value is printed normally.
+
+Pretty-printers are normally named. This makes them easy to manage.
+The @samp{info pretty-printer} command will list all the installed
+pretty-printers with their names.
+If a pretty-printer can handle multiple data types, then its
+@dfn{subprinters} are the printers for the individual data types.
+Each such subprinter has its own name.
+The format of the name is @var{printer-name};@var{subprinter-name}.
+
+Pretty-printers are installed by @dfn{registering} them with @value{GDBN}.
+Typically they are automatically loaded and registered when the corresponding
+debug information is loaded, thus making them available without having to
+do anything special.
+
+There are three places where a pretty-printer can be registered.
+
+@itemize @bullet
+@item
+Pretty-printers registered globally are available when debugging
+all inferiors.
+
+@item
+Pretty-printers registered with a program space are available only
+when debugging that program.
+@xref{Progspaces In Python}, for more details on program spaces in Python.
+
+@item
+Pretty-printers registered with an objfile are loaded and unloaded
+with the corresponding objfile (e.g., shared library).
+@xref{Objfiles In Python}, for more details on objfiles in Python.
+@end itemize
+
+@xref{Selecting Pretty-Printers}, for further information on how
+pretty-printers are selected,
+
+@xref{Writing a Pretty-Printer}, for implementing pretty printers
+for new types.
+
+@node Pretty-Printer Example
+@subsection Pretty-Printer Example
+
+Here is how a C@t{++} @code{std::string} looks without a pretty-printer:
@smallexample
(@value{GDBP}) print s
$2 = "abcd"
@end smallexample
-For implementing pretty printers for new types you should read the Python API
-details (@pxref{Pretty Printing API}).
+@node Pretty-Printer Commands
+@subsection Pretty-Printer Commands
+@cindex pretty-printer commands
+
+@table @code
+@kindex info pretty-printer
+@item info pretty-printer [@var{object-regexp} [@var{name-regexp}]]
+Print the list of installed pretty-printers.
+This includes disabled pretty-printers, which are marked as such.
+
+@var{object-regexp} is a regular expression matching the objects
+whose pretty-printers to list.
+Objects can be @code{global}, the program space's file
+(@pxref{Progspaces In Python}),
+and the object files within that program space (@pxref{Objfiles In Python}).
+@xref{Selecting Pretty-Printers}, for details on how @value{GDBN}
+looks up a printer from these three objects.
+
+@var{name-regexp} is a regular expression matching the name of the printers
+to list.
+
+@kindex disable pretty-printer
+@item disable pretty-printer [@var{object-regexp} [@var{name-regexp}]]
+Disable pretty-printers matching @var{object-regexp} and @var{name-regexp}.
+A disabled pretty-printer is not forgotten, it may be enabled again later.
+
+@kindex enable pretty-printer
+@item enable pretty-printer [@var{object-regexp} [@var{name-regexp}]]
+Enable pretty-printers matching @var{object-regexp} and @var{name-regexp}.
+@end table
+
+Example:
+
+Suppose we have three pretty-printers installed: one from library1.so
+named @code{foo} that prints objects of type @code{foo}, and
+another from library2.so named @code{bar} that prints two types of objects,
+@code{bar1} and @code{bar2}.
+
+@smallexample
+(gdb) info pretty-printer
+library1.so:
+ foo
+library2.so:
+ bar
+ bar1
+ bar2
+(gdb) info pretty-printer library2
+library2.so:
+ bar
+ bar1
+ bar2
+(gdb) disable pretty-printer library1
+1 printer disabled
+2 of 3 printers enabled
+(gdb) info pretty-printer
+library1.so:
+ foo [disabled]
+library2.so:
+ bar
+ bar1
+ bar2
+(gdb) disable pretty-printer library2 bar:bar1
+1 printer disabled
+1 of 3 printers enabled
+(gdb) info pretty-printer library2
+library1.so:
+ foo [disabled]
+library2.so:
+ bar
+ bar1 [disabled]
+ bar2
+(gdb) disable pretty-printer library2 bar
+1 printer disabled
+0 of 3 printers enabled
+(gdb) info pretty-printer library2
+library1.so:
+ foo [disabled]
+library2.so:
+ bar [disabled]
+ bar1 [disabled]
+ bar2
+@end smallexample
+
+Note that for @code{bar} the entire printer can be disabled,
+as can each individual subprinter.
@node Value History
@section Value History
case, @value{GDBN} uses @samp{UTF-8}.
@value{GDBN} can only use certain character sets as its host character
-set. If you type @kbd{@w{set target-charset @key{TAB}@key{TAB}}},
+set. If you type @kbd{@w{set host-charset @key{TAB}@key{TAB}}},
@value{GDBN} will list the host character sets it supports.
@item set charset @var{charset}
@node Supported Languages
@section Supported Languages
-@value{GDBN} supports C, C@t{++}, D, Objective-C, Fortran, Java, Pascal,
+@value{GDBN} supports C, C@t{++}, D, Objective-C, Fortran, Java, OpenCL C, Pascal,
assembly, Modula-2, and Ada.
@c This is false ...
Some @value{GDBN} features may be used in expressions regardless of the
* C:: C and C@t{++}
* D:: D
* Objective-C:: Objective-C
+* OpenCL C:: OpenCL C
* Fortran:: Fortran
* Pascal:: Pascal
* Modula-2:: Modula-2
with certain Objective-C libraries that have a particular hook
function, @code{_NSPrintForDebugger}, defined.
+@node OpenCL C
+@subsection OpenCL C
+
+@cindex OpenCL C
+This section provides information about @value{GDBN}s OpenCL C support.
+
+@menu
+* OpenCL C Datatypes::
+* OpenCL C Expressions::
+* OpenCL C Operators::
+@end menu
+
+@node OpenCL C Datatypes
+@subsubsection OpenCL C Datatypes
+
+@cindex OpenCL C Datatypes
+@value{GDBN} supports the builtin scalar and vector datatypes specified
+by OpenCL 1.1. In addition the half- and double-precision floating point
+data types of the @code{cl_khr_fp16} and @code{cl_khr_fp64} OpenCL
+extensions are also known to @value{GDBN}.
+
+@node OpenCL C Expressions
+@subsubsection OpenCL C Expressions
+
+@cindex OpenCL C Expressions
+@value{GDBN} supports accesses to vector components including the access as
+lvalue where possible. Since OpenCL C is based on C99 most C expressions
+supported by @value{GDBN} can be used as well.
+
+@node OpenCL C Operators
+@subsubsection OpenCL C Operators
+
+@cindex OpenCL C Operators
+@value{GDBN} supports the operators specified by OpenCL 1.1 for scalar and
+vector data types.
+
@node Fortran
@subsection Fortran
@cindex Fortran-specific support in @value{GDBN}
* Stopping Before Main Program:: Debugging the program during elaboration.
* Ada Tasks:: Listing and setting breakpoints in tasks.
* Ada Tasks and Core Files:: Tasking Support when Debugging Core Files
+* Ravenscar Profile:: Tasking Support when using the Ravenscar
+ Profile
* Ada Glitches:: Known peculiarities of Ada mode.
@end menu
Under these circumstances, you should make a backup copy of the core
file before inspecting it with @value{GDBN}.
+@node Ravenscar Profile
+@subsubsection Tasking Support when using the Ravenscar Profile
+@cindex Ravenscar Profile
+
+The @dfn{Ravenscar Profile} is a subset of the Ada tasking features,
+specifically designed for systems with safety-critical real-time
+requirements.
+
+@table @code
+@kindex set ravenscar task-switching on
+@cindex task switching with program using Ravenscar Profile
+@item set ravenscar task-switching on
+Allows task switching when debugging a program that uses the Ravenscar
+Profile. This is the default.
+
+@kindex set ravenscar task-switching off
+@item set ravenscar task-switching off
+Turn off task switching when debugging a program that uses the Ravenscar
+Profile. This is mostly intended to disable the code that adds support
+for the Ravenscar Profile, in case a bug in either @value{GDBN} or in
+the Ravenscar runtime is preventing @value{GDBN} from working properly.
+To be effective, this command should be run before the program is started.
+
+@kindex show ravenscar task-switching
+@item show ravenscar task-switching
+Show whether it is possible to switch from task to task in a program
+using the Ravenscar Profile.
+
+@end table
+
@node Ada Glitches
@subsubsection Known Peculiarities of Ada Mode
@cindex Ada, problems
and the GNU Ada compiler.
@itemize @bullet
-@item
-Currently, the debugger
-has insufficient information to determine whether certain pointers represent
-pointers to objects or the objects themselves.
-Thus, the user may have to tack an extra @code{.all} after an expression
-to get it printed properly.
-
@item
Static constants that the compiler chooses not to materialize as objects in
storage are invisible to the debugger.
for DWARF debugging information, not stabs. And, they do not
currently work for programs using Ada.
-
@node Symbol Errors
@section Errors Reading Symbol Files
automatically if the installed @value{GDBN} is moved to a new
location.
+The data directory may also be specified with the
+@code{--data-directory} command line option.
+@xref{Mode Options}.
+
@node Targets
@chapter Specifying a Debugging Target
@node PowerPC Embedded
@subsection PowerPC Embedded
+@cindex DVC register
+@value{GDBN} supports using the DVC (Data Value Compare) register to
+implement in hardware simple hardware watchpoint conditions of the form:
+
+@smallexample
+(@value{GDBP}) watch @var{ADDRESS|VARIABLE} \
+ if @var{ADDRESS|VARIABLE} == @var{CONSTANT EXPRESSION}
+@end smallexample
+
+The DVC register will be automatically used when @value{GDBN} detects
+such pattern in a condition expression, and the created watchpoint uses one
+debug register (either the @code{exact-watchpoints} option is on and the
+variable is scalar, or the variable has a length of one byte). This feature
+is available in native @value{GDBN} running on a Linux kernel version 2.6.34
+or newer.
+
+When running on PowerPC embedded processors, @value{GDBN} automatically uses
+ranged hardware watchpoints, unless the @code{exact-watchpoints} option is on,
+in which case watchpoints using only one debug register are created when
+watching variables of scalar types.
+
+You can create an artificial array to watch an arbitrary memory
+region using one of the following commands (@pxref{Expressions}):
+
+@smallexample
+(@value{GDBP}) watch *((char *) @var{address})@@@var{length}
+(@value{GDBP}) watch @{char[@var{length}]@} @var{address}
+@end smallexample
+
@value{GDBN} provides the following PowerPC-specific commands:
@table @code
registers. By default, @value{GDBN} selects the calling convention
based on the selected architecture and the provided executable file.
+@item set powerpc exact-watchpoints
+@itemx show powerpc exact-watchpoints
+Allow @value{GDBN} to use only one debug register when watching a variable
+of scalar type, thus assuming that the variable is accessed through the
+address of its first byte.
+
@kindex target dink32
@item target dink32 @var{dev}
DINK32 ROM monitor.
Show whether command line editing is enabled.
@end table
-@xref{Command Line Editing}, for more details about the Readline
+@ifset SYSTEM_READLINE
+@xref{Command Line Editing, , , rluserman, GNU Readline Library},
+@end ifset
+@ifclear SYSTEM_READLINE
+@xref{Command Line Editing},
+@end ifclear
+for more details about the Readline
interface. Users unfamiliar with @sc{gnu} Emacs or @code{vi} are
encouraged to read that chapter.
history facility.
@value{GDBN} uses the @sc{gnu} History library, a part of the Readline
-package, to provide the history facility. @xref{Using History
-Interactively}, for the detailed description of the History library.
+package, to provide the history facility.
+@ifset SYSTEM_READLINE
+@xref{Using History Interactively, , , history, GNU History Library},
+@end ifset
+@ifclear SYSTEM_READLINE
+@xref{Using History Interactively},
+@end ifclear
+for the detailed description of the History library.
To issue a command to @value{GDBN} without affecting certain aspects of
the state which is seen by users, prefix it with @samp{server }
@end table
History expansion assigns special meaning to the character @kbd{!}.
-@xref{Event Designators}, for more details.
+@ifset SYSTEM_READLINE
+@xref{Event Designators, , , history, GNU History Library},
+@end ifset
+@ifclear SYSTEM_READLINE
+@xref{Event Designators},
+@end ifclear
+for more details.
@cindex history expansion, turn on/off
Since @kbd{!} is also the logical not operator in C, history expansion
for implementing operations such as single-stepping the inferior.
@item show debug infrun
Displays the current state of @value{GDBN} inferior debugging.
+@item set debug jit
+@cindex just-in-time compilation, debugging messages
+Turns on or off debugging messages from JIT debug support.
+@item show debug jit
+Displays the current state of @value{GDBN} JIT debugging.
@item set debug lin-lwp
@cindex @sc{gnu}/Linux LWP debug messages
@cindex Linux lightweight processes
@cindex python directory
Python scripts used by @value{GDBN} should be installed in
@file{@var{data-directory}/python}, where @var{data-directory} is
-the data directory as determined at @value{GDBN} startup (@pxref{Data Files}). This directory, known as the @dfn{python directory},
+the data directory as determined at @value{GDBN} startup (@pxref{Data Files}).
+This directory, known as the @dfn{python directory},
is automatically added to the Python Search Path in order to allow
the Python interpreter to locate all scripts installed at this location.
* Python Commands:: Accessing Python from @value{GDBN}.
* Python API:: Accessing @value{GDBN} from Python.
* Auto-loading:: Automatically loading Python code.
+* Python modules:: Python modules provided by @value{GDBN}.
@end menu
@node Python Commands
@menu
* Basic Python:: Basic Python Functions.
-* Exception Handling::
-* Values From Inferior::
+* Exception Handling:: How Python exceptions are translated.
+* Values From Inferior:: Python representation of values.
* Types In Python:: Python representation of types.
* Pretty Printing API:: Pretty-printing values.
* Selecting Pretty-Printers:: How GDB chooses a pretty-printer.
-* Disabling Pretty-Printers:: Disabling broken printers.
+* Writing a Pretty-Printer:: Writing a Pretty-Printer.
* Inferiors In Python:: Python representation of inferiors (processes)
* Threads In Python:: Accessing inferior threads from Python.
* Commands In Python:: Implementing new commands in Python.
@value{GDBN}'s standard output. If the @var{to_string} parameter is
@code{True}, then output will be collected by @code{gdb.execute} and
returned as a string. The default is @code{False}, in which case the
-return value is @code{None}.
+return value is @code{None}. If @var{to_string} is @code{True}, the
+@value{GDBN} virtual terminal will be temporarily set to unlimited width
+and height, and its pagination will be disabled; @pxref{Screen Size}.
@end defun
@findex gdb.breakpoints
@samp{print object} is a valid parameter name.
If the named parameter does not exist, this function throws a
-@code{RuntimeError}. Otherwise, the parameter's value is converted to
-a Python value of the appropriate type, and returned.
+@code{gdb.error} (@pxref{Exception Handling}). Otherwise, the
+parameter's value is converted to a Python value of the appropriate
+type, and returned.
@end defun
@findex gdb.history
and count backward from the last element (i.e., the most recent element) to
find the value to return. If @var{number} is zero, then @value{GDBN} will
return the most recent element. If the element specified by @var{number}
-doesn't exist in the value history, a @code{RuntimeError} exception will be
+doesn't exist in the value history, a @code{gdb.error} exception will be
raised.
If no exception is raised, the return value is always an instance of
convenience variable (@pxref{Convenience Vars}) as a @code{gdb.Value}.
@end defun
+@findex gdb.post_event
+@defun post_event event
+Put @var{event}, a callable object taking no arguments, into
+@value{GDBN}'s internal event queue. This callable will be invoked at
+some later point, during @value{GDBN}'s event processing. Events
+posted using @code{post_event} will be run in the order in which they
+were posted; however, there is no way to know when they will be
+processed relative to other events inside @value{GDBN}.
+
+@value{GDBN} is not thread-safe. If your Python program uses multiple
+threads, you must be careful to only call @value{GDBN}-specific
+functions in the main @value{GDBN} thread. @code{post_event} ensures
+this. For example:
+
+@smallexample
+(@value{GDBP}) python
+>import threading
+>
+>class Writer():
+> def __init__(self, message):
+> self.message = message;
+> def __call__(self):
+> gdb.write(self.message)
+>
+>class MyThread1 (threading.Thread):
+> def run (self):
+> gdb.post_event(Writer("Hello "))
+>
+>class MyThread2 (threading.Thread):
+> def run (self):
+> gdb.post_event(Writer("World\n"))
+>
+>MyThread1().start()
+>MyThread2().start()
+>end
+(@value{GDBP}) Hello World
+@end smallexample
+@end defun
+
@findex gdb.write
@defun write string
Print a string to @value{GDBN}'s paginated standard output stream.
never returned.
@end defun
+@findex gdb.solib_name
+@defun solib_name address
+Return the name of the shared library holding the given @var{address}
+as a string, or @code{None}.
+@end defun
+
+@findex gdb.decode_line
+@defun decode_line @r{[}expression@r{]}
+Return locations of the line specified by @var{expression}, or of the
+current line if no argument was given. This function returns a Python
+tuple containing two elements. The first element contains a string
+holding any unparsed section of @var{expression} (or @code{None} if
+the expression has been fully parsed). The second element contains
+either @code{None} or another tuple that contains all the locations
+that match the expression represented as @code{gdb.Symtab_and_line}
+objects (@pxref{Symbol Tables In Python}). If @var{expression} is
+provided, it is decoded the way that @value{GDBN}'s inbuilt
+@code{break} or @code{edit} commands do (@pxref{Specify Location}).
+@end defun
+
@node Exception Handling
@subsubsection Exception Handling
@cindex python exceptions
NameError: name 'foo' is not defined
@end smallexample
-@value{GDBN} errors that happen in @value{GDBN} commands invoked by Python
-code are converted to Python @code{RuntimeError} exceptions. User
-interrupt (via @kbd{C-c} or by typing @kbd{q} at a pagination
-prompt) is translated to a Python @code{KeyboardInterrupt}
-exception. If you catch these exceptions in your Python code, your
-exception handler will see @code{RuntimeError} or
-@code{KeyboardInterrupt} as the exception type, the @value{GDBN} error
-message as its value, and the Python call stack backtrace at the
-Python statement closest to where the @value{GDBN} error occured as the
+@value{GDBN} errors that happen in @value{GDBN} commands invoked by
+Python code are converted to Python exceptions. The type of the
+Python exception depends on the error.
+
+@ftable @code
+@item gdb.error
+This is the base class for most exceptions generated by @value{GDBN}.
+It is derived from @code{RuntimeError}, for compatibility with earlier
+versions of @value{GDBN}.
+
+If an error occurring in @value{GDBN} does not fit into some more
+specific category, then the generated exception will have this type.
+
+@item gdb.MemoryError
+This is a subclass of @code{gdb.error} which is thrown when an
+operation tried to access invalid memory in the inferior.
+
+@item KeyboardInterrupt
+User interrupt (via @kbd{C-c} or by typing @kbd{q} at a pagination
+prompt) is translated to a Python @code{KeyboardInterrupt} exception.
+@end ftable
+
+In all cases, your exception handler will see the @value{GDBN} error
+message as its value and the Python call stack backtrace at the Python
+statement closest to where the @value{GDBN} error occured as the
traceback.
@findex gdb.GdbError
Again, @code{bar} will also be a @code{gdb.Value} object.
+A @code{gdb.Value} that represents a function can be executed via
+inferior function call. Any arguments provided to the call must match
+the function's prototype, and must be provided in the order specified
+by that prototype.
+
+For example, @code{some_val} is a @code{gdb.Value} instance
+representing a function that takes two integers as arguments. To
+execute this function, call it like so:
+
+@smallexample
+result = some_val (10,20)
+@end smallexample
+
+Any values returned from a function call will be stored as a
+@code{gdb.Value}.
+
The following attributes are provided:
@table @code
@defivar Value type
The type of this @code{gdb.Value}. The value of this attribute is a
-@code{gdb.Type} object.
+@code{gdb.Type} object (@pxref{Types In Python}).
+@end defivar
+
+@defivar Value dynamic_type
+The dynamic type of this @code{gdb.Value}. This uses C@t{++} run-time
+type information (@acronym{RTTI}) to determine the dynamic type of the
+value. If this value is of class type, it will return the class in
+which the value is embedded, if any. If this value is of pointer or
+reference to a class type, it will compute the dynamic type of the
+referenced object, and return a pointer or reference to that type,
+respectively. In all other cases, it will return the value's static
+type.
+
+Note that this feature will only work when debugging a C@t{++} program
+that includes @acronym{RTTI} for the object in question. Otherwise,
+it will just return the static type of the value as in @kbd{ptype foo}
+(@pxref{Symbols, ptype}).
@end defivar
@end table
The following methods are provided:
@table @code
+@defmethod Value __init__ @var{val}
+Many Python values can be converted directly to a @code{gdb.Value} via
+this object initializer. Specifically:
+
+@table @asis
+@item Python boolean
+A Python boolean is converted to the boolean type from the current
+language.
+
+@item Python integer
+A Python integer is converted to the C @code{long} type for the
+current architecture.
+
+@item Python long
+A Python long is converted to the C @code{long long} type for the
+current architecture.
+
+@item Python float
+A Python float is converted to the C @code{double} type for the
+current architecture.
+
+@item Python string
+A Python string is converted to a target string, using the current
+target encoding.
+
+@item @code{gdb.Value}
+If @code{val} is a @code{gdb.Value}, then a copy of the value is made.
+
+@item @code{gdb.LazyString}
+If @code{val} is a @code{gdb.LazyString} (@pxref{Lazy Strings In
+Python}), then the lazy string's @code{value} method is called, and
+its result is used.
+@end table
+@end defmethod
+
@defmethod Value cast type
Return a new instance of @code{gdb.Value} that is the result of
casting this instance to the type described by @var{type}, which must
value pointed to by @code{foo}.
@end defmethod
+@defmethod Value dynamic_cast type
+Like @code{Value.cast}, but works as if the C@t{++} @code{dynamic_cast}
+operator were used. Consult a C@t{++} reference for details.
+@end defmethod
+
+@defmethod Value reinterpret_cast type
+Like @code{Value.cast}, but works as if the C@t{++} @code{reinterpret_cast}
+operator were used. Consult a C@t{++} reference for details.
+@end defmethod
+
@defmethod Value string @r{[}encoding@r{]} @r{[}errors@r{]} @r{[}length@r{]}
If this @code{gdb.Value} represents a string, then this method
converts the contents to a Python string. Otherwise, this method will
@end table
@end defmethod
+@defmethod Type array @var{n1} @r{[}@var{n2}@r{]}
+Return a new @code{gdb.Type} object which represents an array of this
+type. If one argument is given, it is the inclusive upper bound of
+the array; in this case the lower bound is zero. If two arguments are
+given, the first argument is the lower bound of the array, and the
+second argument is the upper bound of the array. An array's length
+must not be negative, but the bounds can be.
+@end defmethod
+
@defmethod Type const
Return a new @code{gdb.Type} object which represents a
@code{const}-qualified variant of this type.
Return a Python @code{Tuple} object that contains two elements: the
low bound of the argument type and the high bound of that type. If
the type does not have a range, @value{GDBN} will raise a
-@code{RuntimeError} exception.
+@code{gdb.error} exception (@pxref{Exception Handling}).
@end defmethod
@defmethod Type reference
convenience functions.
@end table
+Further support for types is provided in the @code{gdb.types}
+Python module (@pxref{gdb.types}).
+
@node Pretty Printing API
@subsubsection Pretty Printing API
If the result is not one of these types, an exception is raised.
@end defop
+@value{GDBN} provides a function which can be used to look up the
+default pretty-printer for a @code{gdb.Value}:
+
+@findex gdb.default_visualizer
+@defun default_visualizer value
+This function takes a @code{gdb.Value} object as an argument. If a
+pretty-printer for this value exists, then it is returned. If no such
+printer exists, then this returns @code{None}.
+@end defun
+
@node Selecting Pretty-Printers
@subsubsection Selecting Pretty-Printers
The Python list @code{gdb.pretty_printers} contains an array of
functions or callable objects that have been registered via addition
-as a pretty-printer.
+as a pretty-printer. Printers in this list are called @code{global}
+printers, they're available when debugging all inferiors.
Each @code{gdb.Progspace} contains a @code{pretty_printers} attribute.
Each @code{gdb.Objfile} also contains a @code{pretty_printers}
attribute.
-A function on one of these lists is passed a single @code{gdb.Value}
+Each function on these lists is passed a single @code{gdb.Value}
argument and should return a pretty-printer object conforming to the
interface definition above (@pxref{Pretty Printing API}). If a function
cannot create a pretty-printer for the value, it should return
@value{GDBN} first checks the @code{pretty_printers} attribute of each
@code{gdb.Objfile} in the current program space and iteratively calls
-each enabled function (@pxref{Disabling Pretty-Printers})
-in the list for that @code{gdb.Objfile} until it receives
-a pretty-printer object.
+each enabled lookup routine in the list for that @code{gdb.Objfile}
+until it receives a pretty-printer object.
If no pretty-printer is found in the objfile lists, @value{GDBN} then
searches the pretty-printer list of the current program space,
calling each enabled function until an object is returned.
and iterated over sequentially until the end of the list, or a printer
object is returned.
+For various reasons a pretty-printer may not work.
+For example, the underlying data structure may have changed and
+the pretty-printer is out of date.
+
+The consequences of a broken pretty-printer are severe enough that
+@value{GDBN} provides support for enabling and disabling individual
+printers. For example, if @code{print frame-arguments} is on,
+a backtrace can become highly illegible if any argument is printed
+with a broken printer.
+
+Pretty-printers are enabled and disabled by attaching an @code{enabled}
+attribute to the registered function or callable object. If this attribute
+is present and its value is @code{False}, the printer is disabled, otherwise
+the printer is enabled.
+
+@node Writing a Pretty-Printer
+@subsubsection Writing a Pretty-Printer
+@cindex writing a pretty-printer
+
+A pretty-printer consists of two parts: a lookup function to detect
+if the type is supported, and the printer itself.
+
Here is an example showing how a @code{std::string} printer might be
-written:
+written. @xref{Pretty Printing API}, for details on the API this class
+must provide.
@smallexample
-class StdStringPrinter:
+class StdStringPrinter(object):
"Print a std::string"
- def __init__ (self, val):
+ def __init__(self, val):
self.val = val
- def to_string (self):
+ def to_string(self):
return self.val['_M_dataplus']['_M_p']
- def display_hint (self):
+ def display_hint(self):
return 'string'
@end smallexample
example above might be written.
@smallexample
-def str_lookup_function (val):
-
+def str_lookup_function(val):
lookup_tag = val.type.tag
- regex = re.compile ("^std::basic_string<char,.*>$")
if lookup_tag == None:
return None
- if regex.match (lookup_tag):
- return StdStringPrinter (val)
-
+ regex = re.compile("^std::basic_string<char,.*>$")
+ if regex.match(lookup_tag):
+ return StdStringPrinter(val)
return None
@end smallexample
this code might appear in @code{gdb.libstdcxx.v6}:
@smallexample
-def register_printers (objfile):
- objfile.pretty_printers.add (str_lookup_function)
+def register_printers(objfile):
+ objfile.pretty_printers.add(str_lookup_function)
@end smallexample
@noindent
@smallexample
import gdb.libstdcxx.v6
-gdb.libstdcxx.v6.register_printers (gdb.current_objfile ())
+gdb.libstdcxx.v6.register_printers(gdb.current_objfile())
@end smallexample
-@node Disabling Pretty-Printers
-@subsubsection Disabling Pretty-Printers
-@cindex disabling pretty-printers
+The previous example illustrates a basic pretty-printer.
+There are a few things that can be improved on.
+The printer doesn't have a name, making it hard to identify in a
+list of installed printers. The lookup function has a name, but
+lookup functions can have arbitrary, even identical, names.
-For various reasons a pretty-printer may not work.
-For example, the underlying data structure may have changed and
-the pretty-printer is out of date.
+Second, the printer only handles one type, whereas a library typically has
+several types. One could install a lookup function for each desired type
+in the library, but one could also have a single lookup function recognize
+several types. The latter is the conventional way this is handled.
+If a pretty-printer can handle multiple data types, then its
+@dfn{subprinters} are the printers for the individual data types.
-The consequences of a broken pretty-printer are severe enough that
-@value{GDBN} provides support for enabling and disabling individual
-printers. For example, if @code{print frame-arguments} is on,
-a backtrace can become highly illegible if any argument is printed
-with a broken printer.
+The @code{gdb.printing} module provides a formal way of solving these
+problems (@pxref{gdb.printing}).
+Here is another example that handles multiple types.
-Pretty-printers are enabled and disabled by attaching an @code{enabled}
-attribute to the registered function or callable object. If this attribute
-is present and its value is @code{False}, the printer is disabled, otherwise
-the printer is enabled.
+These are the types we are going to pretty-print:
+
+@smallexample
+struct foo @{ int a, b; @};
+struct bar @{ struct foo x, y; @};
+@end smallexample
+
+Here are the printers:
+
+@smallexample
+class fooPrinter:
+ """Print a foo object."""
+
+ def __init__(self, val):
+ self.val = val
+
+ def to_string(self):
+ return ("a=<" + str(self.val["a"]) +
+ "> b=<" + str(self.val["b"]) + ">")
+
+class barPrinter:
+ """Print a bar object."""
+
+ def __init__(self, val):
+ self.val = val
+
+ def to_string(self):
+ return ("x=<" + str(self.val["x"]) +
+ "> y=<" + str(self.val["y"]) + ">")
+@end smallexample
+
+This example doesn't need a lookup function, that is handled by the
+@code{gdb.printing} module. Instead a function is provided to build up
+the object that handles the lookup.
+
+@smallexample
+import gdb.printing
+
+def build_pretty_printer():
+ pp = gdb.printing.RegexpCollectionPrettyPrinter(
+ "my_library")
+ pp.add_printer('foo', '^foo$', fooPrinter)
+ pp.add_printer('bar', '^bar$', barPrinter)
+ return pp
+@end smallexample
+
+And here is the autoload support:
+
+@smallexample
+import gdb.printing
+import my_library
+gdb.printing.register_pretty_printer(
+ gdb.current_objfile(),
+ my_library.build_pretty_printer())
+@end smallexample
+
+Finally, when this printer is loaded into @value{GDBN}, here is the
+corresponding output of @samp{info pretty-printer}:
+
+@smallexample
+(gdb) info pretty-printer
+my_library.so:
+ my_library
+ foo
+ bar
+@end smallexample
@node Inferiors In Python
@subsubsection Inferiors In Python
stack (@pxref{Frames,,Stack frames}). The @code{gdb.Frame} class
represents a frame in the stack. A @code{gdb.Frame} object is only valid
while its corresponding frame exists in the inferior's stack. If you try
-to use an invalid frame object, @value{GDBN} will throw a @code{RuntimeError}
-exception.
+to use an invalid frame object, @value{GDBN} will throw a @code{gdb.error}
+exception (@pxref{Exception Handling}).
Two @code{gdb.Frame} objects can be compared for equality with the @code{==}
operator, like:
Return the selected frame object. (@pxref{Selection,,Selecting a Frame}).
@end defun
+@findex gdb.newest_frame
+@defun newest_frame
+Return the newest frame object for the selected thread.
+@end defun
+
@defun frame_stop_reason_string reason
Return a string explaining the reason why @value{GDBN} stopped unwinding
frames, as expressed by the given @var{reason} code (an integer, see the
@end defmethod
@defmethod Frame type
-Returns the type of the frame. The value can be one of
-@code{gdb.NORMAL_FRAME}, @code{gdb.DUMMY_FRAME}, @code{gdb.SIGTRAMP_FRAME}
-or @code{gdb.SENTINEL_FRAME}.
+Returns the type of the frame. The value can be one of:
+@table @code
+@item gdb.NORMAL_FRAME
+An ordinary stack frame.
+
+@item gdb.DUMMY_FRAME
+A fake stack frame that was created by @value{GDBN} when performing an
+inferior function call.
+
+@item gdb.INLINE_FRAME
+A frame representing an inlined function. The function was inlined
+into a @code{gdb.NORMAL_FRAME} that is older than this one.
+
+@item gdb.SIGTRAMP_FRAME
+A signal trampoline frame. This is the frame created by the OS when
+it calls into a signal handler.
+
+@item gdb.ARCH_FRAME
+A fake stack frame representing a cross-architecture call.
+
+@item gdb.SENTINEL_FRAME
+This is like @code{gdb.NORMAL_FRAME}, but it is only used for the
+newest frame.
+@end table
@end defmethod
@defmethod Frame unwind_stop_reason
Python code can manipulate breakpoints via the @code{gdb.Breakpoint}
class.
-@defmethod Breakpoint __init__ spec @r{[}type@r{]} @r{[}wp_class@r{]}
+@defmethod Breakpoint __init__ spec @r{[}type@r{]} @r{[}wp_class@r{]} @r{[}internal@r{]}
Create a new breakpoint. @var{spec} is a string naming the
location of the breakpoint, or an expression that defines a
watchpoint. The contents can be any location recognized by the
command. The optional @var{type} denotes the breakpoint to create
from the types defined later in this chapter. This argument can be
either: @code{BP_BREAKPOINT} or @code{BP_WATCHPOINT}. @var{type}
-defaults to @code{BP_BREAKPOINT}. The optional @var{wp_class}
+defaults to @code{BP_BREAKPOINT}. The optional @var{internal} argument
+allows the breakpoint to become invisible to the user. The breakpoint
+will neither be reported when created, nor will it be listed in the
+output from @code{info breakpoints} (but will be listed with the
+@code{maint info breakpoints} command). The optional @var{wp_class}
argument defines the class of watchpoint to create, if @var{type} is
-defined as @code{BP_WATCHPOINT}. If a watchpoint class is not
-provided, it is assumed to be a @var{WP_WRITE} class.
+@code{BP_WATCHPOINT}. If a watchpoint class is not provided, it is
+assumed to be a @var{WP_WRITE} class.
@end defmethod
The available watchpoint types represented by constants are defined in the
inferior leaves the scope of that watchpoint.
@end defmethod
+@defmethod Breakpoint delete
+Permanently deletes the @value{GDBN} breakpoint. This also
+invalidates the Python @code{Breakpoint} object. Any further access
+to this object's attributes or methods will raise an error.
+@end defmethod
+
@defivar Breakpoint enabled
This attribute is @code{True} if the breakpoint is enabled, and
@code{False} otherwise. This attribute is writable.
writable.
@end defivar
+@defivar Breakpoint visible
+This attribute tells whether the breakpoint is visible to the user
+when set, or when the @samp{info breakpoints} command is run. This
+attribute is not writable.
+@end defivar
+
The available types are represented by constants defined in the @code{gdb}
module:
Auto-loading can be enabled or disabled.
@table @code
-@kindex maint set python auto-load
-@item maint set python auto-load [yes|no]
-Enable or disable the Python auto-loading feature.
+@kindex set auto-load-scripts
+@item set auto-load-scripts [yes|no]
+Enable or disable the auto-loading of Python scripts.
-@kindex maint show python auto-load
-@item maint show python auto-load
-Show whether Python auto-loading is enabled or disabled.
+@kindex show auto-load-scripts
+@item show auto-load-scripts
+Show whether auto-loading of Python scripts is enabled or disabled.
@end table
When reading an auto-loaded file, @value{GDBN} sets the
for example, this GCC macro:
@example
-/* Note: The "MS" section flags are to remote duplicates. */
+/* Note: The "MS" section flags are to remove duplicates. */
#define DEFINE_GDB_SCRIPT(script_name) \
asm("\
.pushsection \".debug_gdb_scripts\", \"MS\",@@progbits,1\n\
top of the source tree to the source search path.
@end itemize
+@node Python modules
+@subsection Python modules
+@cindex python modules
+
+@value{GDBN} comes with a module to assist writing Python code.
+
+@menu
+* gdb.printing:: Building and registering pretty-printers.
+* gdb.types:: Utilities for working with types.
+@end menu
+
+@node gdb.printing
+@subsubsection gdb.printing
+@cindex gdb.printing
+
+This module provides a collection of utilities for working with
+pretty-printers.
+
+@table @code
+@item PrettyPrinter (@var{name}, @var{subprinters}=None)
+This class specifies the API that makes @samp{info pretty-printer},
+@samp{enable pretty-printer} and @samp{disable pretty-printer} work.
+Pretty-printers should generally inherit from this class.
+
+@item SubPrettyPrinter (@var{name})
+For printers that handle multiple types, this class specifies the
+corresponding API for the subprinters.
+
+@item RegexpCollectionPrettyPrinter (@var{name})
+Utility class for handling multiple printers, all recognized via
+regular expressions.
+@xref{Writing a Pretty-Printer}, for an example.
+
+@item register_pretty_printer (@var{obj}, @var{printer})
+Register @var{printer} with the pretty-printer list of @var{obj}.
+@end table
+
+@node gdb.types
+@subsubsection gdb.types
+@cindex gdb.types
+
+This module provides a collection of utilities for working with
+@code{gdb.Types} objects.
+
+@table @code
+@item get_basic_type (@var{type})
+Return @var{type} with const and volatile qualifiers stripped,
+and with typedefs and C@t{++} references converted to the underlying type.
+
+C@t{++} example:
+
+@smallexample
+typedef const int const_int;
+const_int foo (3);
+const_int& foo_ref (foo);
+int main () @{ return 0; @}
+@end smallexample
+
+Then in gdb:
+
+@smallexample
+(gdb) start
+(gdb) python import gdb.types
+(gdb) python foo_ref = gdb.parse_and_eval("foo_ref")
+(gdb) python print gdb.types.get_basic_type(foo_ref.type)
+int
+@end smallexample
+
+@item has_field (@var{type}, @var{field})
+Return @code{True} if @var{type}, assumed to be a type with fields
+(e.g., a structure or union), has field @var{field}.
+
+@item make_enum_dict (@var{enum_type})
+Return a Python @code{dictionary} type produced from @var{enum_type}.
+@end table
+
@node Interpreters
@chapter Command Interpreters
@cindex command interpreters
@cindex TUI key bindings
The TUI installs several key bindings in the readline keymaps
-(@pxref{Command Line Editing}). The following key bindings
-are installed for both TUI mode and the @value{GDBN} standard mode.
+@ifset SYSTEM_READLINE
+(@pxref{Command Line Editing, , , rluserman, GNU Readline Library}).
+@end ifset
+@ifclear SYSTEM_READLINE
+(@pxref{Command Line Editing}).
+@end ifclear
+The following key bindings are installed for both TUI mode and the
+@value{GDBN} standard mode.
@table @kbd
@kindex C-x C-a
Function name.
@item @var{file}
File name of the source file where the function lives.
+@item @var{fullname}
+The full file name of the source file where the function lives.
@item @var{line}
Line number corresponding to the @code{$pc}.
+@item @var{from}
+The shared library where this function is defined. This is only given
+if the frame's function is not known.
@end table
If invoked without arguments, this command prints a backtrace for the
@subheading The @code{-data-read-memory} Command
@findex -data-read-memory
+This command is deprecated, use @code{-data-read-memory-bytes} instead.
+
@subsubheading Synopsis
@smallexample
(gdb)
@end smallexample
+@subheading The @code{-data-read-memory-bytes} Command
+@findex -data-read-memory-bytes
+
+@subsubheading Synopsis
+
+@smallexample
+ -data-read-memory-bytes [ -o @var{byte-offset} ]
+ @var{address} @var{count}
+@end smallexample
+
+@noindent
+where:
+
+@table @samp
+@item @var{address}
+An expression specifying the address of the first memory word to be
+read. Complex expressions containing embedded white space should be
+quoted using the C convention.
+
+@item @var{count}
+The number of bytes to read. This should be an integer literal.
+
+@item @var{byte-offset}
+The offsets in bytes relative to @var{address} at which to start
+reading. This should be an integer literal. This option is provided
+so that a frontend is not required to first evaluate address and then
+perform address arithmetics itself.
+
+@end table
+
+This command attempts to read all accessible memory regions in the
+specified range. First, all regions marked as unreadable in the memory
+map (if one is defined) will be skipped. @xref{Memory Region
+Attributes}. Second, @value{GDBN} will attempt to read the remaining
+regions. For each one, if reading full region results in an errors,
+@value{GDBN} will try to read a subset of the region.
+
+In general, every single byte in the region may be readable or not,
+and the only way to read every readable byte is to try a read at
+every address, which is not practical. Therefore, @value{GDBN} will
+attempt to read all accessible bytes at either beginning or the end
+of the region, using a binary division scheme. This heuristic works
+well for reading accross a memory map boundary. Note that if a region
+has a readable range that is neither at the beginning or the end,
+@value{GDBN} will not read it.
+
+The result record (@pxref{GDB/MI Result Records}) that is output of
+the command includes a field named @samp{memory} whose content is a
+list of tuples. Each tuple represent a successfully read memory block
+and has the following fields:
+
+@table @code
+@item begin
+The start address of the memory block, as hexadecimal literal.
+
+@item end
+The end address of the memory block, as hexadecimal literal.
+
+@item offset
+The offset of the memory block, as hexadecimal literal, relative to
+the start address passed to @code{-data-read-memory-bytes}.
+
+@item contents
+The contents of the memory block, in hex.
+
+@end table
+
+
+
+@subsubheading @value{GDBN} Command
+
+The corresponding @value{GDBN} command is @samp{x}.
+
+@subsubheading Example
+
+@smallexample
+(gdb)
+-data-read-memory-bytes &a 10
+^done,memory=[@{begin="0xbffff154",offset="0x00000000",
+ end="0xbffff15e",
+ contents="01000000020000000300"@}]
+(gdb)
+@end smallexample
+
+
+@subheading The @code{-data-write-memory-bytes} Command
+@findex -data-write-memory-bytes
+
+@subsubheading Synopsis
+
+@smallexample
+ -data-write-memory-bytes @var{address} @var{contents}
+@end smallexample
+
+@noindent
+where:
+
+@table @samp
+@item @var{address}
+An expression specifying the address of the first memory word to be
+read. Complex expressions containing embedded white space should be
+quoted using the C convention.
+
+@item @var{contents}
+The hex-encoded bytes to write.
+
+@end table
+
+@subsubheading @value{GDBN} Command
+
+There's no corresponding @value{GDBN} command.
+
+@subsubheading Example
+
+@smallexample
+(gdb)
+-data-write-memory-bytes &a "aabbccdd"
+^done
+(gdb)
+@end smallexample
+
+
@c %%%%%%%%%%%%%%%%%%%%%%%%%%%% SECTION %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@node GDB/MI Tracepoint Commands
@section @sc{gdb/mi} Tracepoint Commands
@samp{display_hint} field in the output of @code{-var-list-children}
@item thread-info
Indicates presence of the @code{-thread-info} command.
+@item data-read-memory-bytes
+Indicates presense of the @code{-data-read-memory-bytes} and the
+@code{-data-write-memory-bytes} commands.
@end table
execution, which means that @value{GDBN} will accept further commands
while the target is running.
+@item reverse
+Indicates that the target is capable of reverse execution.
+@xref{Reverse Execution}, for more information.
+
@end table
@subheading The @code{-list-thread-groups} Command
@c inc-hist.texinfo
@c Use -I with makeinfo to point to the appropriate directory,
@c environment var TEXINPUTS with TeX.
+@ifclear SYSTEM_READLINE
@include rluser.texi
@include inc-hist.texinfo
+@end ifclear
@node Formatting Documentation
determined by the @value{GDBN} internal gdbarch functions
@code{DEPRECATED_REGISTER_RAW_SIZE} and @code{gdbarch_register_name}. The
specification of several standard @samp{g} packets is specified below.
+
+When reading registers from a trace frame (@pxref{Analyze Collected
+Data,,Using the Collected Data}), the stub may also return a string of
+literal @samp{x}'s in place of the register data digits, to indicate
+that the corresponding register has not been collected, thus its value
+is unavailable. For example, for an architecture with 4 registers of
+4 bytes each, the following reply indicates to @value{GDBN} that
+registers 0 and 2 have not been collected, while registers 1 and 3
+have been collected, and both have zero value:
+
+@smallexample
+-> @code{g}
+<- @code{xxxxxxxx00000000xxxxxxxx00000000}
+@end smallexample
+
@item E @var{NN}
for an error.
@end table
@subsection ARM Features
@cindex target descriptions, ARM features
-The @samp{org.gnu.gdb.arm.core} feature is required for ARM targets.
+The @samp{org.gnu.gdb.arm.core} feature is required for non-M-profile
+ARM targets.
It should contain registers @samp{r0} through @samp{r13}, @samp{sp},
@samp{lr}, @samp{pc}, and @samp{cpsr}.
+For M-profile targets (e.g. Cortex-M3), the @samp{org.gnu.gdb.arm.core}
+feature is replaced by @samp{org.gnu.gdb.arm.m-profile}. It should contain
+registers @samp{r0} through @samp{r13}, @samp{sp}, @samp{lr}, @samp{pc},
+and @samp{xpsr}.
+
The @samp{org.gnu.gdb.arm.fpa} feature is optional. If present, it
should contain registers @samp{f0} through @samp{f7} and @samp{fps}.
@samp{ymm0h} through @samp{ymm7h} for i386
@item
@samp{ymm0h} through @samp{ymm15h} for amd64
-@item
@end itemize
The @samp{org.gnu.gdb.i386.linux} feature is optional. It should