hello everyone
i try to debug a program, which have been installed by makefile.
it have a binary file of OpenDPI_demo.o and a shell shellscript OpenDPI_demo.
when i gdb OpenDPI_demo.o,i have a problem. i can't run it. the error is:
Starting program: /home/lx/ntop/test/opendpi/src/examples/OpenDPI_demo/OpenDPI_demo.o
/bin/bash: /home/lx/ntop/test/opendpi/src/examples/OpenDPI_demo/OpenDPI_demo.o：can't execute the binary file.
please tell me why. actually i can run the program by ./OpenDPI_demo.
thank you.
Based on the extension, the file is an object file. It is used by the linker (alongside other object files) to produce an executable. It's the real executable the one you want to run/debug.
This is another example of difficulties encountered with programs using libtool.
the file OpenDPI_demo alongside OpenDPI_demo.o is actually, as you said, a shell script which wraps the execution of the real compiled file, probably in .libs/OpenDPI_demo.
libtool needs this wrapper to adjust the runtime library paths and such so that you can execute the program transparently, as if it was actually installed on your system.
The way to correctly debug this application is not
/home/lx/ntop/test/opendpi $ gdb src/examples/OpenDPI_demo/.libs/OpenDPI_demo
but rather using libtool --mode=execute on the shell script, like the following (it's an example):
/home/lx/ntop/test/opendpi $ ./libtool --mode=execute gdb --args \
src/examples/OpenDPI_demo/OpenDPI_demo -f capture.pcap
Suggest you use
gdb OpenDPI_demo
instead
In your makefile if it depens on the object, make it depend on OpenDPI_demo, e.g.
Related
I was trying to execute Makefile and wanted to execute a C program with it. First, how can I include test.c file for makefile?
I've placed makefile in root directly as there will be other .c files later added.
Can anyone hep me executing this?
File structure:
Makefile code so far not working (it will work if I place it inside src still not getting the output of file.)
# -o : object file
Test: test.c
gcc -o Test test.c
Glad if anyone can help or suggest anything!
I don't usually follow links but I was curious so I did so. Your problem isn't related to make or makefiles or how your code is built. As best as can be determined from the screenshots, all that is fine.
The problem is that when you try to run the program, it's not found.
When the shell tries to run a program it looks in the directories contained in the PATH environment variable, and only there. It won't look in the current directory, unless the current directory is on the PATH.
So when you type the name of a program without a pathname to tell the shell where to find it, such as Test (by the way it's not a good idea to call your program Test because there is a system program named test on POSIX systems and it can cause confusion), it will search the directories on PATH for Test, and if the program is not found there it will fail.
If you don't want to rely on PATH you need to give the shell the pathname of the program you want to run. So you can run .\Test instead (on POSIX systems it would be ./Test), to tell the shell that you want to run Test from the current directory.
I once tried to compile a C program I made that was for a chess game (thanks to YouTube's Bluefever Software for the tutorial), but when I went to compile the program, I executed this line of code:
C:\TDM-GCC-64\>gcc Chess/chess.c Chess/init.c -o chess
The compiling worked (there were no syntax errors or anything), but when I got to my file directory, I saw this (circled in blue):
An unexpected application (but there were no viruses!):
How did this happen? It may had something to do with the line I was compiling, but what is the "intel" behind this?
It is normal for the compiler to generate an application!
What is surprising is the location for the executable, it should have been generated in the parent directory:
C:\TDM-GCC-64\> gcc Chess/chess.c Chess/init.c -o chess
The explanation is interesting:
You are using the Windows operating system, where the filenames are case insensitive.
You instructed gcc to generate the executable into chess, but this is the name of the Chess directory. In this case, gcc generates the executable in the named directory and gives it a name that is the basename of the first source file chess.c -> chess.
Furthermore, the application name really is chess.exe in Windows, but the default setting for the file manager is to not display file extensions. This is a very unfortunate choice. I suggest you change this setting in the Windows/File Explorer Options window to always show file extensions. This will allow you to distinguish chess.c, chess.exe and chess.h more easily.
You have a Makefile in the Chess directory, you should use the make command to build the executable:
C:\TDM-GCC-64\> make -C Chess
Or simply cd to the Chess subdirectory and type:
C:\TDM-GCC-64\Chess> make
That's the file you told the compiler to make.
The -o option to gcc is the output file. In this case, you told it to create an executable file named chess. And that's exactly what was created.
The compiler is automatically creating an executable file while compiling.
I'm trying to find a way to convert simple C code to NASM assembly. I have tried using objconv and downloaded and unzipped and built it since I am using a MAC; however, it doesn't seem to be working. I keep getting "-bash: objconv: command not found". Does anyone know another way or can help me solve the -bash error.
Bash is the program that takes the words you type in a terminal and launches other programs. If it is reporting an error, it is because it cannot find the program you want to run (at least in this case).
You need to either find a pre-packaged installation of objconv, or you need to do the work to "integrate" your copy of objconv yourself.
If you can identify the executable you want to run (probably called objconv) you need to add that to your path. The easiest way (if it is just for you) is to verify that your ~/.bashrc or ~/.bashprofile has a line that looks something like
PATH=$PATH:${HOME}/bin
Don't worry if it doesn't look exactly the same. Just make sure there's a ${HOME}/bin or ~/bin (~ is the short version of ${HOME}).
If you have that then type the commands
cd ~/bin
ln -fs ../path/to/objconv
and you will create a soft link (a type of file) in your home binary directory, and the program should be available to the command line.
If you create the file, and nothing above has any errors, but it is not available to the command line, you might need to set the executable bit on your "real" (not link) copy of objconv.
If this doesn't work, by now you should be well primed for a better, more specific question.
If you have gcc installed, try gcc -masm=intel -S source.c to generate assembly files in a syntax very similar to that of MASM.
I'm on a Mac and in terminal I'm compiling my program
gcc -Wall -g -o example example.c
it compiles (there are no errors), but when I try to provide command line arguments
example 5 hello how are you
terminal responds with "-bash: example: command not found"
how am supposed to provide the arguments I want to provide after compiling?
Run it like this with path:
./example 5 hello how are you
Unless the directory where the example binary is part of the PATH variable, what you have won't work even if the binary you are running is in the current directory.
It is not a compilation issue, but an issue with your shell. The current directory is not in your PATH (look with echo $PATH and use which to find out how the shell uses it for some particular program, e.g. which gcc).
I suggest testing your program with an explicit file path for the program like
./example 5 hello how are you
You could perhaps edit your ~/.bashrc to add . at the end of your PATH. There are pro and conses (in particular some possible security issues if your current directory happens to be sometimes a "malicious" one like perhaps /tmp might be : bad guys might put there a gcc which is a symlink to /bin/rm so you need to add . at the end of your PATH if you do).
Don't forget to learn how to use a debugger (like gdb). This skill is essential when coding in C (or in C++). Perhaps consider also upgrading your gcc (Apple don"t like much its current GPLv3 license so don't distribute the recent one; try just gcc -v and notice that the latest released GCC is today 4.8.1).
./example 5 Hello how are you is the syntax you're looking for.
This article lends a good explanation as to why this is important.
Basically, when you hit Enter, the shell checks to see if the first set of characters is an absolute path. If it's not, it checks the PATH variable to find executables with the name of the command you are trying to run. If it's found, it will be run, but otherwise it will crash and burn and you will become very sad.
I am trying to figure out what I am doing wrong when trying to use just flex in a Cmake file to build a shared lib.
i basically have the following
find_package(FLEX)
FLEX_TARGET(Test ../src/test.l ../src/test.c)
set(SRC_FILES mysource.c ${FLEX_Test_OUTPUTS})
add_libary(testlib ${SRC_FILES})
target_link_libraries(testlib crypto c ${FLEX_LIBRARIES})
this is giving me a problem saying it cant find ../src/test.c
any ideas how I can make sure Lex ran first? secondly,how can i pass my -L and -d options to lex (like I am doing in my normal, pre-cmake version of this makefile)
Why do you want output file to be in the source dir?
I'd recommend using ${CMAKE_CURRENT_BINARY_DIR}:
FLEX_TARGET(Test ../src/test.l ${CMAKE_CURRENT_BINARY_DIR}/../src/test.c)
As for
any ideas how I can make sure Lex ran first?
you don't need to do it, CMake can guess this dependency by it's own. I think the problem is either in using source dir for output file, or the ../src dir doesn't exist before flex runs.
secondly,how can i pass my -L and -d options to lex
List them after the output parameter:
FLEX_TARGET(Test ../src/test.l ${CMAKE_CURRENT_BINARY_DIR}/../src/test.c -L -d)