C++ lldb debug with input file - c++

I'm attempting to debug my program with lldb beacuse I'm getting a segmentation fault when entering a specific input that should would. I give my program the input through a text file and normally I write this command to run it:
./program <tests/test1.maze> program.out
How do I run the debugger whilst still passing in the file? Haven't been able to find anything that says how to do this.

(lldb) process launch -i <file>
Use the help command to view all available options.
(lldb) help process launch

Related

Debugging Gtk-CRITICAL

When running my program, I am getting Gtk-CRITICAL error on the Terminal, which I'd like to fix.
I found this link through Google, but turns out there is no such option in gdb:
igor#IgorReinCloud ~/dbhandler/Debug/dbhandler $ gdb --g-fatal-warnings dbhandler
gdb: unrecognized option '--g-fatal-warnings'
Use `gdb --help' for a complete list of options.
I also tried to set a breakpoint on the g_log() function, but the execution didn't stop there.
What am I missing?
Thank you.
you can use G_DEBUG=fatal-criticals, so that the application execution breaks at the first location where a critical is emitted.
To run inside gdb, run G_DEBUG=fatal-criticals gdb my-app, and as usual, do run inside gdb to run your application.
You may also set the G_DEBUG environment variable with export (if in bash). Thus you could do export G_DEBUG=fatal-criticals, and then run your app as gdb my-app, which will have the same effect.
See https://docs.gtk.org/glib/running.html for more details
What am I missing?
Looks like that after reading the link, you were confused that gdb should have --g-fatal-warnings option for debugging Gtk applications. This is not the case because gdb is not Gtk application, but your program is. So you should run your program with --g-fatal-warnings option inside gdb like this:
gdb --args dbhandler --g-fatal-warnings
See also related question How do I run a program with commandline args using gdb within a bash script?.

Xcode 8.3: Run target with input from file

I wrote a simple C++ program that requires some input to run. In the terminal I simply run in ./myProgram < fileWithData.txt. However I could not figure out how to specify and input file for the target executed in Xcode. I used the command line project. Of course I could use a different target, for example run Terminal.app and then pass it the executable with the input file but then I can no longer debug it.
This question: Cannot get lldb to read file input explains how to set the input path in lldb, but I could not find a way to specify lldb commands that are executed before the process is started.
I don't think there's a way to do this entirely from within Xcode. However if you set the Run Scheme in Xcode to the launch mode "Wait for executable to be launched," hit run, and then run your program from Terminal.app with the appropriate piping, the Xcode-embedded lldb will connect to it.

How to use gdb to reverse engineer an ELF which runs another program?

I am a beginner and got some trouble in RE.
I have an ELF 'bomb' and an unknown file 'model.abc'.
The correct way to run bomb is:
bomb model.abc
Now I want to use gdb to see the value of some addresses when running it. Can any one help me?
First start gdb from a shell prompt:
$ gdb bomb
Then run your program from the (gdb) prompt with the command line you want:
(gdb) run model.abc
You need to launch your program this way because gdb doesn't allow you to specify command line arguments for your program on the gdb command line.
Another, more convenient way of debugging a program with arguments:
gdb --args program <arguments>
If you don't have symbols, you'll have to start from the entry point. To figure our where it is, use:
(gdb) info file
Symbols from "/.../tesprog".
Local exec file:
`/.../tesprog', file type elf32-i386.
Entry point: 0x804abc0
Then you can set breakpoint on it before running:
break *0x804abc0
Note that the entry will be most often the library startup code (ctr0.s), it might take a while to get to the actual code written by the programmer.

What needs to be done to get a distributable program from Eclipse?

I’ve produced a C++ program in Eclipse running on Redhat, which compiles and runs fine through Eclipse.
I thought that to run it separately to Eclipse you use the build artifact which is in the directory set via the project’s properties.
However this executable doesn’t run (I know it’s an executable as I’ve set it to be an executable via the project’s properties and it shows up as such via the ls command and the file explorer).
When attempting to run it using the executable’s name, I get the error:
bash: <filename>: command not found
When attempting to run it as a bash file:
<filename>: <filename>: cannot execute binary file
And when running it with "./" before the file name, nothing happens. Nothing new appears in the running processes and the terminal just goes to the next line as though I’d just pressed enter with no command.
Any help?
You've more or less figure out the first error yourself. when you just run <filename> , it is not in your PATH environment variable, so you get "command not found". You have to give a full or relative path when to the program in order to run it, even if you're in the same directory as the program - you run it with ./<filename>
When you do run your program, it appears to just exit as soon as you start it - we can't help much with that without knowing what the program does or see some code.
You can do some debugging, e.g. after the program just exits run echo $? to see if it exited with a particular exit value, or run your program using the strace tool to see what it does (or do it the usual way, insert printf debugging, or debug it with gdb)

Load a new exe with gdb

I am currently trying to make use of gdb to disassemble an exe, and from my home, I start the application like such:
gdb "c:\file.exe"
And gdb starts and loads that file automatically.
Now the problem is that from where I am atm, the command prompt is disabled and thus I cannot run the terminal window with the filename as the argument.
The only thing I think can do atm is open the gdb.exe file directly and then load the exe with a command or something, from gdb itself.
Is there a command I can use to load the exe to debug from within the application itself rather than passing it as an argument?
(gdb) <some command> "c:\file.exe"
(gdb)file c:\file.exe
To start debugging it , use the file command, as #Arkaitz Jimenez said
If your file.exe is a running process, you can use the attach command