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Remove extraneous text accidentally incorporated from ddb(4).

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Rearrange the order of the initial description to correspond with the
detailed description below.
Reinstate reference to Topsy, at the risk of confusing people whose
understanding of English grammar is better than of American folklore.
This commit is contained in:
Greg Lehey 2004-01-02 05:16:50 +00:00
parent 65a690ef74
commit 8da0249608
1 changed files with 21 additions and 20 deletions
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41
share/man/man4/gdb.4
View File

@ -34,10 +34,6 @@
.Cd "makeoptions DEBUG=-g"
.Cd "options DDB"
.Cd "options GDB_REMOTE_CHAT"
.Pp
To prevent activation of the debugger on kernel
.Xr panic 9 :
.Cd "options DDB_UNATTENDED"
.Sh DESCRIPTION
The
.Nm
@ -49,13 +45,18 @@ kernel environment.
It can be used in a number of ways:
.Bl -bullet
.It
It can be used to examine the memory of the processor on which it runs.
.It
It can be used to analyse a processor dump after a panic.
.It
It can be used to debug another system interactively via a serial or firewire
link.
In this mode, the processor can be stopped and single stepped.
.It
It can be used to examine the memory of the processor on which it runs.
.It
It can be used to analyse a processor dump after a panic.
With a firewire link, it can be used to examine the memory of a remote system
without the participation of that system.
In this mode, the processor cannot be stopped and single stepped, but it can be
of use when the remote system has crashed and is no longer responding.
.El
.Pp
When used for remote debugging,
@ -81,7 +82,7 @@ First, ensure you have a copy of the debug macros in the directory:
This command performs some transformations on the macros installed in
.Pa /usr/src/tools/debugscripts
to adapt them to the local environment.
.Ss "Debugging a Local Machine"
.Ss "Inspecting the environment of the local machine"
To look at and change the contents of the memory of the system you are running
on,
.Pp
@ -102,15 +103,15 @@ The system does not stop (obviously), so a number of things will not work.
You can set breakpoints, but you cannot
.Dq continue
execution, so they will not work.
.Ss "Debugging a Crash Dump"
By default, crash dumps are stored in the directory
.Ss "Debugging a crash dump"
by default, crash dumps are stored in the directory
.Pa /var/crash .
Investigate them from the kernel build directory with:
.Pp
.Dl "gdb -k kernel.debug /var/crash/vmcore.29"
.Pp
In this mode, the system is obviously stopped, so you can only look at it.
.Ss "Debugging a Live System with a Remote Link"
.Ss "Debugging a live system with a remote link"
In the following discussion, the term
.Dq "local system"
refers to the system running the debugger, and
@ -125,7 +126,7 @@ The option
enables the debugging machine stop the debugged machine once a connection has
been established by pressing
.Ql ^C .
.Ss "Debugging a Live System with a Remote Serial Link"
.Ss "Debugging a live system with a remote serial link"
When using a serial port for the remote link on the i386 platform, the serial
port must be identified by setting the flag bit
.Li 0x80
@ -141,7 +142,7 @@ should be:
To share a console and debug connection on a serial line, use the
.Cd "options GDB_REMOTE_CHAT"
option.
.Ss "Debugging a Live System with a Remote Firewire Link"
.Ss "Debugging a live system with a remote firewire link"
As with serial debugging, to debug a live system with a firewire link, the
kernel must be compiled with the option
.Cd "options DDB" .
@ -292,7 +293,7 @@ Then establish connection with:
0xc21bd378 in ?? ()
.Ed
.El
.Ss "Non-Cooperative Debugging a Live System with a Remote Firewire Link"
.Ss "Non-cooperative debugging a live system with a remote firewire link"
In addition to the conventional debugging via firewire described in the previous
section, it is possible to debug a remote system without its cooperation, once
an initial connection has been established.
@ -350,7 +351,7 @@ so
commands also work.
This section discusses only the extensions for kernel debugging that get
installed in the kernel build directory.
.Ss "Debugging Environment"
.Ss "Debugging environment"
The following macros manipulate the debugging environment:
.Bl -tag -width indent
.It Ic ddb
@ -392,7 +393,7 @@ and
.Ic trf
are convenience commands which invoke
.Ic tr .
.Ss "The Current Process Environment"
.Ss "The current process environment"
The following macros are convenience functions intended to make things easier
than the standard
.Xr gdb 1
@ -440,7 +441,7 @@ Single step 1 instruction (over calls) and show next instruction.
.It Ic zs
Single step 1 instruction (through calls) and show next instruction.
.El
.Ss "Examining Other Processes"
.Ss "Examining other processes"
The following macros access other processes.
The
.Nm
@ -473,7 +474,7 @@ of the stack of the process previously selected with
Show some PCB contents of the process
.Ar proc .
.El
.Ss "Examining Data Structures"
.Ss "Examining data structures"
You can use standard
.Xr gdb 1
commands to look at most data structures.
@ -511,7 +512,7 @@ Show some information of the
pointed to by the local variable
.Va vp .
.El
.Ss "Miscellaneous Macros"
.Ss "Miscellaneous macros"
.Bl -tag -width indent
.It Ic checkmem
Check unallocated memory for modifications.
@ -586,7 +587,7 @@ run the link at more than 9600 bps.
Firewire connections do not have this problem.
.Pp
The debugging macros
.Dq "just grew" .
.Dq "just growed" .
In general, the person who wrote them did so while looking for a specific
problem, so they may not be general enough, and they may behave badly when used
in ways for which they were not intended, even if those ways make sense.