refcard.tex

gdb-6.0 linux 下的调试工具

watch {\it expr}&set a watchpoint for expression {\it expr}\cr
catch {\it event}&break at {\it event}, which may be {\tt catch}, {\tt throw},
{\tt exec}, {\tt fork}, {\tt vfork}, {\tt load}, or {\tt unload}.\cr
\cr
info break&show defined breakpoints\cr
info watch&show defined watchpoints\cr
\cr
clear&delete breakpoints at next instruction\cr
clear \opt{\it file\tt:}{\it fun}&delete breakpoints at entry to {\it fun}()\cr
clear \opt{\it file\tt:}{\it line}&delete breakpoints on source line \cr
delete \opt{{\it n}}&delete breakpoints
\opt{or breakpoint {\it n}}\cr
\cr
disable \opt{{\it n}}&disable breakpoints
\opt{or breakpoint {\it n}}
\cr
enable \opt{{\it n}}&enable breakpoints 
\opt{or breakpoint {\it n}}
\cr
enable once \opt{{\it n}}&enable breakpoints \opt{or breakpoint {\it n}}; 
disable again when reached
\cr
enable del \opt{{\it n}}&enable breakpoints \opt{or breakpoint {\it n}}; 
delete when reached
\cr
\cr
ignore {\it n} {\it count}&ignore breakpoint {\it n}, {\it count}
times\cr
\cr
commands {\it n}\par
\qquad \opt{\tt silent}\par
\qquad {\it command-list}&execute GDB {\it command-list} every time breakpoint {\it n} is reached. \opt{{\tt silent} suppresses default
display}\cr
end&end of {\it command-list}\cr
\endsec

\sec Program Stack;
backtrace \opt{\it n}\par
bt \opt{\it n}&print trace of all frames in stack; or of {\it n}
frames---innermost if {\it n}{\tt >0}, outermost if {\it n}{\tt <0}\cr
frame \opt{\it n}&select frame number {\it n} or frame at address {\it
n}; if no {\it n}, display current frame\cr
up {\it n}&select frame {\it n} frames up\cr
down {\it n}&select frame {\it n} frames down\cr
info frame \opt{\it addr}&describe selected frame, or frame at
{\it addr}\cr
info args&arguments of selected frame\cr
info locals&local variables of selected frame\cr
info reg \opt{\it rn}$\ldots$\par
info all-reg \opt{\it rn}&register values \opt{for regs {\it rn\/}} in
selected frame; {\tt all-reg} includes floating point\cr
\endsec

\vfill\eject
\sec Execution Control;
continue \opt{\it count}\par
c \opt{\it count}&continue running; if {\it count} specified, ignore
this breakpoint next {\it count} times\cr
\cr
step \opt{\it count}\par
s \opt{\it count}&execute until another line reached; repeat {\it count} times if
specified\cr
stepi \opt{\it count}\par
si \opt{\it count}&step by machine instructions rather than source
lines\cr
\cr
next \opt{\it count}\par
n \opt{\it count}&execute next line, including any function calls\cr
nexti \opt{\it count}\par
ni \opt{\it count}&next machine instruction rather than source
line\cr
\cr
until \opt{\it location}&run until next instruction (or {\it
location})\cr
finish&run until selected stack frame returns\cr
return \opt{\it expr}&pop selected stack frame without executing
\opt{setting return value}\cr
signal {\it num}&resume execution with signal {\it s} (none if {\tt 0})\cr
jump {\it line}\par
jump *{\it address}&resume execution at specified {\it line} number or
{\it address}\cr
set var={\it expr}&evaluate {\it expr} without displaying it; use for
altering program variables\cr
\endsec

\sec Display;
print \opt{\tt/{\it f}\/} \opt{\it expr}\par
p \opt{\tt/{\it f}\/} \opt{\it expr}&show value of {\it expr} \opt{or
last value \tt \$} according to format {\it f}:\cr
\qquad x&hexadecimal\cr
\qquad d&signed decimal\cr
\qquad u&unsigned decimal\cr
\qquad o&octal\cr
\qquad t&binary\cr
\qquad a&address, absolute and relative\cr
\qquad c&character\cr
\qquad f&floating point\cr
call \opt{\tt /{\it f}\/} {\it expr}&like {\tt print} but does not display
{\tt void}\cr
x \opt{\tt/{\it Nuf}\/} {\it expr}&examine memory at address {\it expr};
optional format spec follows slash\cr
\quad {\it N}&count of how many units to display\cr
\quad {\it u}&unit size; one of\cr
&{\tt\qquad b}\ individual bytes\cr
&{\tt\qquad h}\ halfwords (two bytes)\cr
&{\tt\qquad w}\ words (four bytes)\cr
&{\tt\qquad g}\ giant words (eight bytes)\cr
\quad {\it f}&printing format.  Any {\tt print} format, or\cr
&{\tt\qquad s}\ null-terminated string\cr
&{\tt\qquad i}\ machine instructions\cr
disassem \opt{\it addr}&display memory as machine instructions\cr
\endsec

\sec Automatic Display;
display \opt{\tt/\it f\/} {\it expr}&show value of {\it expr} each time
program stops \opt{according to format {\it f}\/}\cr
display&display all enabled expressions on list\cr
undisplay {\it n}&remove number(s) {\it n} from list of
automatically displayed expressions\cr
disable disp {\it n}&disable display for expression(s) number {\it
n}\cr
enable disp {\it n}&enable display for expression(s) number {\it
n}\cr
info display&numbered list of display expressions\cr
\endsec

\vfill\eject

\sec Expressions;
{\it expr}&an expression in C, C++, or Modula-2 (including function calls), or:\cr
{\it addr\/}@{\it len}&an array of {\it len} elements beginning at {\it
addr}\cr
{\it file}::{\it nm}&a variable or function {\it nm} defined in {\it
file}\cr
$\tt\{${\it type}$\tt\}${\it addr}&read memory at {\it addr} as specified
{\it type}\cr
\$&most recent displayed value\cr
\${\it n}&{\it n}th displayed value\cr
\$\$&displayed value previous to \$\cr
\$\${\it n}&{\it n}th displayed value back from \$\cr
\$\_&last address examined with {\tt x}\cr
\$\_\_&value at address \$\_\cr
\${\it var}&convenience variable; assign any value\cr
\cr
show values \opt{{\it n}}&show last 10 values \opt{or surrounding
\${\it n}}\cr
show conv&display all convenience variables\cr
\endsec

\sec Symbol Table;
info address {\it s}&show where symbol {\it s} is stored\cr
info func \opt{\it regex}&show names, types of defined functions
(all, or matching {\it regex})\cr
info var \opt{\it regex}&show names, types of global variables (all,
or matching {\it regex})\cr
whatis \opt{\it expr}\par
ptype \opt{\it expr}&show data type of {\it expr} \opt{or \tt \$}
without evaluating; {\tt ptype} gives more detail\cr
ptype {\it type}&describe type, struct, union, or enum\cr
\endsec

\sec GDB Scripts;
source {\it script}&read, execute GDB commands from file {\it
script}\cr
\cr
define {\it cmd}\par
\qquad {\it command-list}&create new GDB command {\it cmd}; 
execute script defined by {\it command-list}\cr
end&end of {\it command-list}\cr
document {\it cmd}\par
\qquad {\it help-text}&create online documentation 
for new GDB command {\it cmd}\cr
end&end of {\it help-text}\cr
\endsec

\sec Signals;
handle {\it signal} {\it act}&specify GDB actions for {\it signal}:\cr
\quad print&announce signal\cr
\quad noprint&be silent for signal\cr
\quad stop&halt execution on signal\cr
\quad nostop&do not halt execution\cr
\quad pass&allow your program to handle signal\cr
\quad nopass&do not allow your program to see signal\cr
info signals&show table of signals, GDB action for each\cr
\endsec

\sec Debugging Targets;
target {\it type} {\it param}&connect to target machine, process, or file\cr
help target&display available targets\cr
attach {\it param}&connect to another process\cr
detach&release target from GDB control\cr
\endsec

\vfill\eject
\sec Controlling GDB;
set {\it param} {\it value}&set one of GDB's internal parameters\cr
show {\it param}&display current setting of parameter\cr
\xtra{\rm Parameters understood by {\tt set} and {\tt show}:}
\quad complaint {\it limit}&number of messages on unusual symbols\cr
\quad confirm {\it on/off}&enable or disable cautionary queries\cr
\quad editing {\it on/off}&control {\tt readline} command-line editing\cr
\quad height {\it lpp}&number of lines before pause in display\cr
\quad language {\it lang}&Language for GDB expressions ({\tt auto}, {\tt c} or
{\tt modula-2})\cr
\quad listsize {\it n}&number of lines shown by {\tt list}\cr
\quad prompt {\it str}&use {\it str} as GDB prompt\cr
\quad radix {\it base}&octal, decimal, or hex number representation\cr
\quad verbose {\it on/off}&control messages when loading
symbols\cr
\quad width {\it cpl}&number of characters before line folded\cr
\quad write {\it on/off}&Allow or forbid patching binary, core files
(when reopened with {\tt exec} or {\tt core})
\cr
\quad history $\ldots$\par
\quad h $\ldots$&groups with the following options:\cr
\quad h exp {\it off/on}&disable/enable {\tt readline} history expansion\cr
\quad h file {\it filename}&file for recording GDB command history\cr
\quad h size {\it size}&number of commands kept in history list\cr
\quad h save {\it off/on}&control use of external file for
command history\cr
\cr
\quad print $\ldots$\par
\quad p $\ldots$&groups with the following options:\cr
\quad p address {\it on/off}&print memory addresses in stacks,
values\cr
\quad p  array {\it off/on}&compact or attractive format for
arrays\cr
\quad p demangl {\it on/off}&source (demangled) or internal form for C++
symbols\cr
\quad p asm-dem {\it on/off}&demangle C++ symbols in
machine-instruction output\cr
\quad p elements {\it limit}&number of array elements to display\cr
\quad p object {\it on/off}&print C++ derived types for objects\cr
\quad p pretty {\it off/on}&struct display: compact or indented\cr
\quad p union {\it on/off}&display of union members\cr
\quad p vtbl {\it off/on}&display of C++ virtual function
tables\cr
\cr
show commands&show last 10 commands\cr
show commands {\it n}&show 10 commands around number {\it n}\cr
show commands +&show next 10 commands\cr
\endsec

\sec Working Files;
file \opt{\it file}&use {\it file} for both symbols and executable;
with no arg, discard both\cr
core \opt{\it file}&read {\it file} as coredump; or discard\cr
exec \opt{\it file}&use {\it file} as executable only; or discard\cr
symbol \opt{\it file}&use symbol table from {\it file}; or discard\cr
load {\it file}&dynamically link {\it file\/} and add its symbols\cr
add-sym {\it file} {\it addr}&read additional symbols from {\it file},
dynamically loaded at {\it addr}\cr
info files&display working files and targets in use\cr
path {\it dirs}&add {\it dirs} to front of path searched for
executable and symbol files\cr
show path&display executable and symbol file path\cr
info share&list names of shared libraries currently loaded\cr
\endsec

\vfill\eject
\sec Source Files;
dir {\it names}&add directory {\it names} to front of source path\cr
dir&clear source path\cr
show dir&show current source path\cr
\cr
list&show next ten lines of source\cr
list -&show previous ten lines\cr
list {\it lines}&display source surrounding {\it lines}, 
specified as:\cr
\quad{\opt{\it file\tt:}\it num}&line number \opt{in named file}\cr
\quad{\opt{\it file\tt:}\it function}&beginning of function \opt{in
named file}\cr
\quad{\tt +\it off}&{\it off} lines after last printed\cr
\quad{\tt -\it off}&{\it off} lines previous to last printed\cr
\quad{\tt*\it address}&line containing {\it address}\cr
list {\it f},{\it l}&from line {\it f} to line {\it l}\cr
info line {\it num}&show starting, ending addresses of compiled code for
source line {\it num}\cr
info source&show name of current source file\cr
info sources&list all source files in use\cr
forw {\it regex}&search following source lines for {\it regex}\cr
rev {\it regex}&search preceding source lines for {\it regex}\cr
\endsec

\sec GDB under GNU Emacs;
M-x gdb&run GDB under Emacs\cr
\ctl{h} m&describe GDB mode\cr
M-s&step one line ({\tt step})\cr
M-n&next line ({\tt next})\cr
M-i&step one instruction ({\tt stepi})\cr
\ctl{c} \ctl{f}&finish current stack frame ({\tt finish})\cr
M-c&continue ({\tt cont})\cr
M-u&up {\it arg} frames ({\tt up})\cr
M-d&down {\it arg} frames ({\tt down})\cr
\ctl{x} \&&copy number from point, insert at end\cr
\ctl{x} SPC&(in source file) set break at point\cr
\endsec

\sec GDB License;
show copying&Display GNU General Public License\cr
show warranty&There is NO WARRANTY for GDB.  Display full no-warranty
statement.\cr 
\endsec


\vfill
{\smrm\parskip=6pt
Copyright \copyright 1991,'92,'93,'98,2000 Free Software Foundation, Inc. 
Author: Roland H. Pesch

The author assumes no responsibility for any errors on this card.

This card may be freely distributed under the terms of the GNU
General Public License.

Please contribute to development of this card by
annotating it.  Improvements can be sent to [e-mail].

GDB itself is free software; you are welcome to distribute copies of
it under the terms of the GNU General Public License.  There is
absolutely no warranty for GDB.
}
\end