Embedded Operating Systems; Using Gdb With Vxworks - Red Hat ENTERPRISE LINUX 4 - DEBUGGING WITH GDB Manual

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(gdb) x/2x &'cygwin1!__argv'
0x610c0aa8 cygwin1!__argv :
(gdb) x/x 0x10021608
0x10021608:
(gdb) x/s 0x0022fd98
0x22fd98:
Setting a break point within a DLL is possible even before the program starts execution. However,
under these circumstances, gdb can't examine the initial instructions of the function in order to skip
the function's frame set-up code. You can work around this by using "*&" to set the breakpoint at a
raw memory address:
(gdb) break *&'python22!PyOS_Readline'
Breakpoint 1 at 0x1e04eff0
The author of these extensions is not entirely convinced that setting a break point within a shared DLL
like
kernel32.dll

20.2. Embedded Operating Systems

This section describes configurations involving the debugging of embedded operating systems that
are available for several different architectures.
gdb includes the ability to debug programs running on various real-time operating systems.

20.2.1. Using gdb with VxWorks

target vxworks
machinename
A VxWorks system, attached via TCP/IP. The argument
machine name or IP address.
On VxWorks,
load
symbols in gdb.
gdb enables developers to spawn and debug tasks running on networked VxWorks targets from a Unix
host. Already-running tasks spawned from the VxWorks shell can also be debugged. gdb uses code
that runs on both the Unix host and on the VxWorks target. The program
on the Unix host. (It may be installed with the name
programs on the host itself.)
VxWorks-timeout
All VxWorks-based targets now support the option
user, and represents the number of seconds gdb waits for responses to rpc's. You might use
args
this if your VxWorks target is a slow software simulator or is on the far side of a thin network
line.
The following information on connecting to VxWorks was current when this manual was produced;
newer releases of VxWorks may use revised procedures.
0x0022fd98
"/cygdrive/c/mydirectory/myprogram"
is completely safe.
links dynamically on the current target system as well as adding its
filename
args
Chapter 20. Configuration-Specific Information
0x10021608
machinename
, to distinguish it from a gdb for debugging
vxgdb
vxworks-timeout
0x00000000
is the target system's
is installed and executed
gdb
. This option is set by the