I am writing a script that runs GDB and a series of GDB commands.
One of my commands file myfile.elf generates warning messages;
warning: Loadable segment ".func_addrs" outside of ELF segments
warning: Loadable segment ".aux_info" outside of ELF segments
I have tried using the set verbose off command in GDB to try to turn these off but it didn't work.
Does anyone know how I can stop these messages?
Thanks!
There isn't a way to do this in gdb.
You can disable all output using "set logging".
Or you could redirect it to a file, then grep out the offending lines, displaying the rest.
You should be able to suppress the warning messages by simply redirecting stderr to the bit bucket.
Just add 2>/dev/null onto the end of your gdb command.
For example:
gdb -p [Process ID] 2>/dev/null
At least this worked for the warning messages that I was encountering!
Related
I'm not very into unix/linux, I'm using rhat linux with sh, tcsh shells.
What I'm trying to do is to debug lifecycle of the object of the class by breaking on it's default, copy c-tors, on d-tor and on operator=; move operations are not defined neither by compiler or me. I break on these functions and printf some lines and also print backtrace
br /project/src/some_file.c:408
commands
silent
printf "<%p> D E F A U L T c-tor bt:\n", this
bt
cont
end
The thing is there're a lot objects of this class, so there is a lot of output, and nothing helps me to disable output to the terminal, so I want see gdb output only in the file, not in the shell. Is it possible to achieve using sh or tcsh? - I can't really impact on the environment and use some other debugger or shell. The reason I want to disable any output from gdb and process being debugged to the shell is because I believe it slows down gdb and execution of the debugged process, which breaks behavior of debugged application.
Using gdb 8.1. I tried logging options of gdb, redirecting output by
run > somefile
and I tried to run gdb like this
gdb -p 1000 -x breakpoint.txt | tee somefile.txt
Thanks many times!
this link has various option for logging
http://sourceware.org/gdb/onlinedocs/gdb/Logging-Output.html
simple one is
set logging file file
Change the name of the current logfile. The default logfile is gdb.txt.
then
set logging on
Enable logging.
I have a GDB script that is deadreckon'ing up the callstack and blindly calling list and up using gdb 7.2:
gdb -q -batch -x gdb.cmd
gdb.cmd has:
list
up-silently
list
up-silently
[...]
Unfortunately, this will fail if gdb can't find the source file or it is inside a library that wasn't compiled with -g:
gdb.cmd:30: Error in sourced command file:
Line number 63 out of range; /home/ross/tmp.cc has 62 lines.
How can I suppress all errors and continue executing the script even if list or any other command fails?
There isn't a good way from the gdb CLI. The gdb CLI is rather limited.
If your gdb is built against Python, you can do it reasonably easily. Search for the "ignore-errors" script.
I am using gdb to debug NS-2 which is a simulator for network protocols. It takes an .tcl file as input and interpret it. [I think it is an interpreter.]
Some of the code is written in tcl (events and creation of network components) and some in C++ (especially Packet Formats, Agents etc.).
I have created an Agent in C++ and i want to stop it at some function call so that i can see the stack trace and find which other classes have been called before it.
This is what i have done:
There was some error in one of my MyAgent::function and it was giving Segmentation Fault and gdb was stopping there automatically. I could then see the stack trace. I rectified the error.
Now when i run
gdb ./ns
b MyAgent::function()
/*
When i press TAB after writing "b MyA" it gives me all functions
of my class :). when i press enter after above command --
it asks me "Breakpoint on future shared library load" and i say Yes.
I hope this is ok ??
*/
r myfiles/myWireless.tcl
Now it runs and do not stop anywhere. :(
I am sure that this function is being called, because when that Segmentation fault was occuring, it was stopping at that function.
Thanks
You can add a breakpoint in that function:
(gdb) break MyAgent::function()
You must make sure to compile with whatever options are necessary to get debug symbols. On GCC, use the -g or -ggdb options.
You need the -args option to specify the tcl script that will be executed.
Run gdb like this:
gdb -args ./ns path/to/tcl/script.tcl
To enable debug flag to c++ code, if have not done it already, re-configure your ns2 instalation with:
./configure --enable-debug ;# plus any other flags you use for configuring
make clean
make -j 3 ;# -j for faster compiling
make install ;# optional
You can also use the --with-tcldebug=..., for debugging tcl code (You need to install tcldebug first for this option)
when I run gdbserver on uclinux target device blackfin bfin537/stamp it work perfectly but it always generates annoying output
Request to get for unknown register 232
Request to get for unknown register 236
it is extremely annoying since each step out or step in gdb client results several of that error on the output screen terminal RS232 I was recommended to change the bfin compiler version and rebuild gdb server with different version of uclinux ,.... none of them worked and even compiling my code with different versions of bfin-uclinux-gcc didn't solve my problem.
I decided to recompile gdbserver.c and eliminate the line that generates the error but in fact that line does not exists in any of the gdbserver related files for compiling.
I decided to suppress the stderr output of gdb server by running gdbserver :3298 process 1>/dev/null 2>/dev/null but this didn't solve it
how can I configure my gdb client to asks for specific registers (bfin-uclinux-gdb) related to bfin537-stamp?
I think this error originates somewhere else in uclinux system background system processes.
I want to find which process writes in stderr,stdout which I am unaware of It and I want to suppress its outputs?
Shall I change something in the busybox shell or /bin/bash to eliminates all stderr outputs
which means if I send all the parent shell output or stderr to /dev/null
Thanks
In bash, I can use the script command, which dumps everything that shows on the shell to a file, including:
commands typed
PS1 line
stdout and stderr of commands
What is the equivalent in gdb?
I tried to run shell script from inside GDB, but after I hit return, I was in the shell and lost the shell prompt and could not run command any more. Moreover I could not use ctrl+c or ctrl+\ to exit. I needed to force kill the /bin/login tty2 to exit.
If you want to log GDB's output, you can use the GDB logging output commands, eg.
set logging file mylog.txt
set logging on
If you want to redirect your program's output to a file, you can use a redirect, eg.
run myprog > mylog.txt
see the chapter on program IO in the GDB manual for more information
Create a text file, i.e. gdbCommands.txt, with the following commands
set logging on my_log_file\nbt 10\nq
bt 10, indicates the number of lines (function calls) we need from the backtrace, in our example is 10 lines.
Execute gdb using the following command, assuming a core dump file core.2345
gdb -x gdbCommands.txt myApp core.2345
Open my_log_file and inspect backtrace!
howto-redirect-gdb-backtrace-output-to-a-text-file
I have logging enabled using:
set trace-commands on
set pagination off
set logging file $log
and show logging reports (to both to terminal and file):
+show logging
Currently logging to mylog.
Logs will be appended to the log file.
Output will be logged and displayed
If I print the value of a variable that also gets logged (to both to terminal and file):
+p myvar
$2 = 0
But if I do command like where or “info b” all I get logged to the file is:
+where
+info b
Anyone know why or how to fix it?
Have a look at the GDB documentation. Search for "Canned Sequences of Commands". There is a way to save GDB commands in a file and run them with the source command and you can use some GDB commands in these scripts to print information available to GDB (like echo, output and printf).
If you want that output in a file, use set logging file FILE.