I apologize if this seems like a stupid question, but I guess I am more used to packages that come with Makefiles or configure scripts.
I downloaded the Mongoose source tar file from the site, and untarred it.
I then tried to compile an executable out of it using
gcc -g -c mongoose.c -o main.o -lpthread -ldl.
However, after trying to execute, I get the error -bash: ./main.o: cannot execute binary file
When I looked into mongoose.c source, I did not find a main function.
Where can I get the main function so that the Linux mongoose web server can be compiled to work the same way as the Windows mongoose.exe?
Mongoose does come with a Makefile, and will compile as a standalone command-line program. Lua and SQLite are included.
The easiest way to compile the latest version is to cd into the "build" directory and run make unix. I'm not sure about the archived version on the downloads page, but trunk has been pretty stable.
I just checked out a clean copy of Mongoose from github earlier tonight and built it with no problems, so I can confirm that this works (assuming you have any other dependencies set up properly, of course).
It's because mongoose is not supposed to be used standalone, but to "embed" it into your program. You need to create a program which calls the correct function from mongoose.c.
Also, the -c flag to GCC tells it to create an object file, which needs to be linked to create an executable. So you try to execute a file which is not executable.
Related
I’ve recently done a git clone of the wine repository at https://github.com/wine-mirror/wine and downloaded the folders to (~/repo/wine/). I'm trying to run Notepad, but don't know how. I am assuming that to build and compile it, I would need to run main.c from the notepad folder. I’m running GCC v 8.3.0 on Raspbian/Linux 10
With the repo downloaded as shown above, what build commands would I need to run notepad’s main.c from Geanie (or any, currently using Geanie) IDE? Can a single compile and/or build command let me run notepad from Geanie, or am I missing something?
Other details (not needed if what I thought I was going to do can't be done):
I wanted to try to run main.c at (~/repo/wine/programs/main.c), but don’t know how to get GCC to view all of the necessary header files. In my execution instructions window in Geanie, I have
gcc -Wall -c “%f” /home/pi/repo/wine/include
and my build instruction (it won't compile, so this isn't anything I've even gotten to work with yet...)
gcc -Wall -o “%e” “%f” /home/pi/repo/wine/include
When I attempt to compile, I get:
Stdio.h:11:10: fatal error: corecrt_wstdui.h: No such file or directory.
#include <corecrt_wstudio.h>
I went over to the stdio.h and attempted to add a build instruction here as well that also targets the include folder (which is the supposedly missing file), but it won’t compile.
Using cpp -v, I can see my include paths for GCC are as follows:
#include”...” paths:
#include<...> paths:
\usr\lib\gcc\arm-linux-gnueabihf\8\include
\usr\local\include
\usr\lib\gcc\arm-linux-gnueabihf\8\include-fixed
\usr\include\arm-linux-gnueabihf
\usr\include
I wrote a demo using libpq to connect to a PostgreSQL database.
I tried to connect the C file to PostgreSQL by including
#include <libpq-fe.h>
after I added the paths into system variables I:\Program Files\PostgreSQL\12\lib as well as to I:\Program Files\PostgreSQL\12\include and compiled with this command:
gcc -Wall -Wextra -m64 -I "I:\Program Files\PostgreSQL\12\include" -L "I:\Program Files\PostgreSQL\12\lib" testpsql.c -lpq -o testpsql
It first raised three errors, like
libssl-1_1-x64.dll is missing
libintl-8.dll was missing
libcrypto-1_1-x64.dll was missing
After I downloaded these three files and put them into I:\Program Files\PostgreSQL\12\lib, and compiled it again, it shows the error
The application was unable to start correctly (0xc0150002)
when I type testpsql. But if I type ./testpsql on git bash, it works. Anyone can please tell me why?
The code that I used was the first example from here.
Environment: PostgreSQL 12, Windows 10, MinGW64
“Download the DLL files” sounds dangerous. From where?
I would get rid of these files again. Since you probably don't reference these libraries from your code, it must be the dependencies of libpq.dll and are probably found in I:\Program Files\PostgreSQL\12\bin (if you used the EDB installer).
The problem is probably that you the PATH environment variable is different in git bash and in cmd.exe, and in the latter case not all required shared libraries can be found on the PATH. The solution is to change the PATH so that it includes all DLL files the executable requires, not to start copying around files.
It is probably enough to include I:\Program Files\PostgreSQL\12\bin in the PATH. To resolve missing dependencies, use a tool like dependency walker or this replacement.
I wrote a C function to be executed from within PostgreSQL (with a CREATE FUNCTION ... LANGUAGE C; command) but when I do so, it responds 'PQnfields: symbol not found'.
I tried to include the path to where the libpq library is when I compile, like this:
gcc -lpq -fpic -c crossdb.c -I`pg_config --includedir-server` -I /usr/include/ -std=c99
But it didn't work.
I think that it is simply not possible to use libpq to query the database from a function... So if you know how to do it or what is causing this error message, I'd be happy to ear it from you.
You'll have to put the directory containing libpq.so.* on PostgreSQL's shared library path, either by setting LD_LIBRARY_PATH in the server's environment or by adding -Wl,-rpath,/path/to/so to the compile line.
Are you using the PGXS framework to build the shared library? That gives you most of the proper flags automatically.
Look at postgres_fdw's Makefile for inspiration, it links with libpq too.
Taking a step back: are you sure that you need a function called crossdb that calls the client? I would investigate if a foreign table or dblink can do what you are trying to achieve.
So I have source code written in C for the LibIdn2 library. I am looking to port it into C# but running in to some issues along the way and would appreciate some help.
Installed Cygwin along with Make and GCC G++ packages
Successfully able to run the./configure command on the source directory
After this, running the "make" command produces an .exe file.
I have been trying to get a .dll file created but cannot seem to do so using gcc compiler. The command I am running is:
gcc -shared -o idn2.dll src/idn2.c
but it complains that it cant find the header files referenced in the idn2.c source file.
I have checked that in the idn2.h file, dll_Export is defined.
Any ideas how should I proceed? I need to get a dll.
I have some 3rd party libraries and includes (I have copied them to the this location /usr/ssd/include and /usr/ssd/lib) that I need to link with my application. I have just created a test application to see if I can link ok. However, when I try to run my app I get the following message.
./app: error while loading shared libraries: libssdn.so: cannot open shared object file: No such file or directory
On the command line I am compiling like this:
gcc -g -Wall -I/usr/ssd/include -L/usr/ssd/lib -lssdn test_app.c -o app
Everything compiles ok, as I don't get any warnings or errors. However, I get the error when I try and run the app.
In the usr/ssd/lib the library is called libssdn.so
I am been looking for solution and I have read something about -rpath, -Wl and LD_LIBRARY_PATH, but not sure what they are and how to include them when I compile.
I am using Ubuntu 9.04 Linux,
Thanks for any advice,
Test if adding /usr/ssd/lib to your $LD_LIBRARY_PATH helps:
In a shell:
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/ssd/lib
If that solves the problem, make it permanent by adding /usr/ssd/lib to /etc/ld.so.conf or by running
ldconfig -n /usr/ssd/lib
My personal preference is not to bake the location of a shared object into an executable (which is what -rpath would do).
Instead, you should add /usr/ssd/lib to your LD_LIBRARY_PATH at run time. Assuming you are running bash or a bash like shell, do:
export LD_LIBRARY_PATH=/usr/ssd/lib:${LD_LIBRARY_PATH}
and once you do that, you can run your executable.