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Diffstat (limited to 'gdb/doc/gdb.texinfo')
| -rw-r--r-- | gdb/doc/gdb.texinfo | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo index 354b888..9ba56a8 100644 --- a/gdb/doc/gdb.texinfo +++ b/gdb/doc/gdb.texinfo @@ -4472,6 +4472,55 @@ a result of the fatal signal once it saw the signal. To prevent this, you can continue with @samp{signal 0}. @xref{Signaling, ,Giving your Program a Signal}. +@cindex extra signal information +@anchor{extra signal information} + +On some targets, @value{GDBN} can inspect extra signal information +associated with the intercepted signal, before it is actually +delivered to the program being debugged. This information is exported +by the convenience variable @code{$_siginfo}, and consists of data +that is passed by the kernel to the signal handler at the time of the +receipt of a signal. The data type of the information itself is +target dependent. You can see the data type using the @code{ptype +$_siginfo} command. On Unix systems, it typically corresponds to the +standard @code{siginfo_t} type, as defined in the @file{signal.h} +system header. + +Here's an example, on a @sc{gnu}/Linux system, printing the stray +referenced address that raised a segmentation fault. + +@smallexample +@group +(@value{GDBP}) continue +Program received signal SIGSEGV, Segmentation fault. +0x0000000000400766 in main () +69 *(int *)p = 0; +(@value{GDBP}) ptype $_siginfo +type = struct @{ + int si_signo; + int si_errno; + int si_code; + union @{ + int _pad[28]; + struct @{...@} _kill; + struct @{...@} _timer; + struct @{...@} _rt; + struct @{...@} _sigchld; + struct @{...@} _sigfault; + struct @{...@} _sigpoll; + @} _sifields; +@} +(@value{GDBP}) ptype $_siginfo._sifields._sigfault +type = struct @{ + void *si_addr; +@} +(@value{GDBP}) p $_siginfo._sifields._sigfault.si_addr +$1 = (void *) 0x7ffff7ff7000 +@end group +@end smallexample + +Depending on target support, @code{$_siginfo} may also be writable. + @node Thread Stops @section Stopping and Starting Multi-thread Programs @@ -7348,6 +7397,11 @@ to match the format in which the data was printed. @vindex $_exitcode@r{, convenience variable} The variable @code{$_exitcode} is automatically set to the exit code when the program being debugged terminates. + +@item $_siginfo +@vindex $_siginfo@r{, convenience variable} +The variable @code{$_siginfo} is bound to extra signal information +inspection (@pxref{extra signal information}). @end table On HP-UX systems, if you refer to a function or variable name that @@ -14307,6 +14361,14 @@ are: @tab @code{qXfer:spu:write} @tab @code{info spu} +@item @code{read-siginfo-object} +@tab @code{qXfer:siginfo:read} +@tab @code{print $_siginfo} + +@item @code{write-siginfo-object} +@tab @code{qXfer:siginfo:write} +@tab @code{set $_siginfo} + @item @code{get-thread-local-@*storage-address} @tab @code{qGetTLSAddr} @tab Displaying @code{__thread} variables @@ -26879,6 +26941,16 @@ These are the currently defined stub features and their properties: @tab @samp{-} @tab Yes +@item @samp{qXfer:siginfo:read} +@tab No +@tab @samp{-} +@tab Yes + +@item @samp{qXfer:siginfo:write} +@tab No +@tab @samp{-} +@tab Yes + @item @samp{QNonStop} @tab No @tab @samp{-} @@ -26939,6 +27011,14 @@ The remote stub understands the @samp{qXfer:spu:read} packet The remote stub understands the @samp{qXfer:spu:write} packet (@pxref{qXfer spu write}). +@item qXfer:siginfo:read +The remote stub understands the @samp{qXfer:siginfo:read} packet +(@pxref{qXfer siginfo read}). + +@item qXfer:siginfo:write +The remote stub understands the @samp{qXfer:siginfo:write} packet +(@pxref{qXfer siginfo write}). + @item QNonStop The remote stub understands the @samp{QNonStop} packet (@pxref{QNonStop}). @@ -27097,6 +27177,16 @@ annex part of the generic @samp{qXfer} packet must be empty This packet is not probed by default; the remote stub must request it, by supplying an appropriate @samp{qSupported} response (@pxref{qSupported}). +@item qXfer:siginfo:read::@var{offset},@var{length} +@anchor{qXfer siginfo read} +Read contents of the extra signal information on the target +system. The annex part of the generic @samp{qXfer} packet must be +empty (@pxref{qXfer read}). + +This packet is not probed by default; the remote stub must request it, +by supplying an appropriate @samp{qSupported} response +(@pxref{qSupported}). + @item qXfer:spu:read:@var{annex}:@var{offset},@var{length} @anchor{qXfer spu read} Read contents of an @code{spufs} file on the target system. The @@ -27149,6 +27239,7 @@ the stub, or that the object does not support reading. @item qXfer:@var{object}:write:@var{annex}:@var{offset}:@var{data}@dots{} @cindex write data into object, remote request +@anchor{qXfer write} Write uninterpreted bytes into the target's special data area identified by the keyword @var{object}, starting at @var{offset} bytes into the data. @var{data}@dots{} is the binary-encoded data @@ -27161,6 +27252,16 @@ Here are the specific requests of this form defined so far. All formats, listed below. @table @samp +@item qXfer:siginfo:write::@var{offset}:@var{data}@dots{} +@anchor{qXfer siginfo write} +Write @var{data} to the extra signal information on the target system. +The annex part of the generic @samp{qXfer} packet must be +empty (@pxref{qXfer write}). + +This packet is not probed by default; the remote stub must request it, +by supplying an appropriate @samp{qSupported} response +(@pxref{qSupported}). + @item qXfer:spu:write:@var{annex}:@var{offset}:@var{data}@dots{} @anchor{qXfer spu write} Write @var{data} to an @code{spufs} file on the target system. The |