I have installed libusb by using the following command. I am not sure if it was right or not and the command was
sudo apt-get install libusb-dev
Once I have installed (and I am not sure if it has installed or not because I am a novice user of Ubuntu), I want to know how would I use the library, because I write some sample code which uses <libusb.h>, but when I compile that C++ file using
g++ test_libusb.cpp
that throws the following error,
test_libusb.cpp:2:20: fatal error: libusb.h: No such file or directory compilation terminated.
I am clueless what to do. I can't find any source on the Internet to get to the bottom of this...
I want to know two things here:
How do I add the libusb library in C/C++ so I can use <libusb.h>?
What would some sample code be? Only a few lines to see if libusb is working...
Try including it like so:
#include <libusb-1.0/libusb.h>
and then compile it like so:
g++ main.cpp -o main -lusb-1.0
Have a look at http://packages.debian.org/wheezy/i386/libusb-dev/filelist: The file you want to include is usb.h. Also, you'll have to tell the compiler where it can find the compiled library functions: Add -lusb to the compiler command line to make it load libusb.so.
Actually at least in Debian 7.4 (wheezy), and probably in Ubuntu also, there are two distinct libusb packages: libusb-dev (0.1.12-20+nmu1) and libusb-1.0-0-dev (1.0.11-1). Confusingly, they can both be installed concurrently and provide header files in different locations:
$ dpkg -L libusb-dev|grep /usr/include
/usr/include
/usr/include/usb.h
$ dpkg -L libusb-1.0-0-dev|grep /usr/include
/usr/include
/usr/include/libusb-1.0
/usr/include/libusb-1.0/libusb.h
Try #include <usb.h>. The "lib" is part of the Linux naming convention, i.e. library "foo" has header foo.h and is called libfoo-dev in the Debian package structure, and linked as -lfoo, and the compiled library files are called libfoo.a and libfoo.so.
Related
I have just installed hidapi in my Ubuntu 20.04 following the instructions, i.e. by doing
sudo apt install libhidapi-dev
I wrote my program in the file mwe.cpp which contains only this line:
#include <hidapi.h>
and now I want to compile it with
g++ -o mwe.o mwe.cpp
but I get
mwe.cpp:1:10: fatal error: hidapi.h: No such file or directory
How am I supposed to use this module? Sorry for such a basic question but cannot find out.
On Ubuntu based systems, the system package libhidapi-dev installs the include files to /usr/include/hidapi, so either include this (-I/usr/include/hidapi) in your command line or #include <hidapi/hidapi.h>
If that header is not within the standard search path for headers, then you can include it manually with the -I flag e.g.
g++ -I/usr/include/hidapi -o mwe.o mwe.cpp
To locate a file on ubuntu, you can run:
sudo updatedb
locate hidapi.h
> /usr/include/hidapi/hidapi.h
You can view the standard include search path with:
gcc -print-search-dirs
Alternatively, because /usr/include is on the standard search path, you can write your include as <hidapi/hidapi.h>.
How to #include <whatever.h> installed with apt in Ubuntu
If the package installs the header within a directory included in the default search path of your compiler - which is typical - then you can include the header using a relative path from the root of the search path where the header is installed. For example, if the file is in the path /usr/include/x/y.h, then you can include <x/y.h>.
If the package doesn't install the header within the default search path, then you must specify the search path for the compiler when you invoke it, and then include the header relative to the specified include directory. For example, if the file is in the path /opt/custom/x/y.h, then you can include <x/y.h> and specify /opt/custom as a search path for the compiler.
If you use GCC or compatible compiler, and the package supports it, then you can use a program called pkg-config to get the compiler options needed to use the library. Besides the header search path, this also takes care of linking with the library as well as any mandatory compiler options. Example:
pkg-config --libs --cflags libhidapi
I don't know, how do I find the location of hidapi.h?
There are several ways to find out the location of a file. A general tool is the program find. Example:
find / -name=hidapi.h
A more specific tool for learning the paths of files installed by an apt package is apt-file. Alternatively, you can look up the list of files in the https://packages.ubuntu.com/ website.
I'm trying to build the SDL library from the source code. I've downloaded the compressed file (i.e. SDL2-2.0.3.tar.gz) and extracted it. I don't want to install the files in /usr/local. According to this link, I need to change the configure
The last command says "sudo" so we can write it to /usr/local (by
default). You can change this to a different location with the
--prefix option to the configure script. In fact, there are a LOT of good options you can use with configure! Be sure to check out its
--help option for details.
This is what I've done.
mkdir build
cd build
../configure
make
sudo make install
In install folder that I've created are the following files
share
lib
include
bin
Now I would like to run the test files. I've picked this testatomic.c and this is the command line
gcc testatomic.c -o test -I/home/xxxx/Desktop/SDL2-2.0.3/install/include/SDL2 -L/home/xxxx/Desktop/SDL2-2.0.3/install/lib -lSDL2 -lSDL2main
I get this error
error while loading shared libraries: libSDL2-2.0.so.0: cannot open shared object file: No such file or directory
In lib, these are the files
Where is the shared object file?
You're getting error when running resulting program because system's dynamic linker cannot find required library. Program requires libSDL2-2.0.so.0, linker looks for it in system-defined directories (/lib, /usr/lib, ..., - defined in /etc/ld.so.conf), but finds none - hence an error.
To inform linker where you want it to look for libraries, you can define LD_LIBRARY_PATH environment variable, e.g. in your case:
export LD_LIBRARY_PATH="$HOME/Desktop/SDL2-2.0.3/install/lib"
./test
Other ways is installing libraries in standard location, defining LD_LIBRARY_PATH in your .bashrc (or whatever shell you use), or using rpath, e.g. adding -Wl,-rpath=$HOME/Desktop/SDL2-2.0.3/install/lib at the end of your compilation line.
I was able to fix this problem with:
sudo apt install libsdl2-dev
I too had:
./01_hello_SDL: error while loading shared libraries: libSDL2-2.0.so.0: cannot open shared object file: No such file or directory
as a result of compiling the first C++ program (using the SDL headers) as part of the Lazy Foo tutorial. I found out that libSDL2-2.0.so.0 was just using the find command in the GUI. It turned out to be in /usr/local/lib
Then in terminal I typed:
export LD_LIBRARY_PATH="/usr/local/lib"
I checked the value of LD_LIBRARY_PATH using:
echo $LD_LIBRARY_PATH
I recompiled (don't know if that was necessary) and voila, it worked.
I am trying to maintain file history on a server from a client and I have thought of using xdelta for it. There is almost no help online for using xdelta. I gathered a few bits and pieces of code and tried to run it in order to understand it myself but the compiler gives the following error:
fatal error: xdelta3.h: No such file or directory
I have installed xdelta3 using apt-get as well as by downloading .tar from the website.
Here's the header files I included:
#include <xdelta3.h>
#include <xdelta3-main.h>
Any ideas as to what the header files for xdelta are? It will be appreciated if you could also provide some links for learning how to use xdelta since the documentation is insufficient for me.
First of all, be sure that you have -dev package installed as well. On my Debian system I did:
$ sudo apt-get install libxdelta2-dev
Now you should be able to use those xdelta headers. But they can have different naming than you use. You can check it this way:
$ dpkg -L libxdelta2-dev | grep include
For me shows:
/usr/include/edsio_edsio.h
/usr/include/edsio.h
/usr/include/xd_edsio.h
/usr/include/xdelta.h
So you can see that in this case I should use xdelta.h header, no xdelta3.h. Try the same dpkg -L command with your -dev package.
If you have different version of xdelta*-dev package, check output of this command:
pkg-config --list-all | grep delta
For me output is empty, but if you have something like libxdelta in output, be sure to compile your application with these options:
$ gcc $(pkg-config --cflags --libs libxdelta) main.c
UPDATE 1
As for the linking issue you have. I guess you are using gcc, so it automatically uses correct linker for you. The thing is, you should provide library name, which you want to link your program with, as a linker option.
First you should figure out your actual library name:
$ ls -1 /usr/lib | grep xdelta | grep so
You will see something like this:
libxdelta.so
libxdelta.so.2
libxdelta.so.2.0.0
Now you know your library name: it's part of library file name between lib and .so, in this case library name is xdelta.
Now you can link your program with it, using -l option:
$ gcc -lxdelta main.c
You may be also needed to specify path to xdelta library, if it's not a standard one (like /usr/lib/):
$ gcc -L/your/path/to/xdelta/ -lxdelta main.c
UPDATE 2
How to build and use xdelta3.
Obtain sources:
cd /tmp
wget https://xdelta.googlecode.com/files/xdelta3-3.0.8.tar.xz
tar xJvf xdelta3-3.0.8.tar.xz
cd xdelta3-3.0.8/
Build and install:
./configure
make
sudo make install
Check if it works:
cd examples/
make clean
make encode_decode_test
./encode_decode_test
If everything is fine, you should have executable file "encode_decode_test". It's example uses xdelta3. Now you can build your program the same way. See "Makefile" file inside of "examples" directory to get a clue how to build your program. Note that there is no libraries involved now.
I use gsl.
After I compiled my .cpp file and run it, I faced with below error:
error while loading shared libraries: libgsl.so.0: cannot open shared object file: No such file or directory
I found same as this problem in:
https://groups.google.com/forum/#!topic/cortex_var/6vluX7pP0Sk
&
Linux error while loading shared libraries: cannot open shared object file: No such file or directory
&
http://www.gnu.org/software/gsl/manual/html_node/Shared-Libraries.html
And I have done as in the above links wrote but the error is still remained.
Can anyone help me?
To make it work do the following steps
Start Borne Shell
$LD_LIBRARY_PATH= path to your gsl lib folder inside the gsl installation folder
$export LD_LIBRARY_PATH
now run your executable
It should work fine.
First, you need to locate the file (libgsl.so.0). You can do this, for example, by using the find command:
sudo find / -name "libgsl.so.0"
Let us assume, the file is located in /usr/local/lib.
(If the file has not been found, install the corresponding package or download the source, build it and install it.)
Now, you have two options:
(1) Quick & Dirty:
LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib
export LD_LIBRARY_PATH
This adds the path of the library to an environment variable. The disadvantage of this option is, that it is only valid for the current session. It will not work for other users. It will not work once you log off and on again.
(2) Permanent:
Review your /etc/ld.so.conf. If /usr/local/lib is not listed there, add it. Now, run ldconfig to detect the shared object file and add it to some system-wide index.
I got the same error with Krita on Arch Linux. I made a symlink with
ln /usr/lib/libgsl.so /usr/lib/libgsl.so.0
and that fixed it.
In my experience, fastStructure depends on gsl 1.6 but not the latest version.
wget http://gnu.mirror.vexxhost.com/gsl/gsl-1.6.tar.gz
tar -zxvf gsl-1.6.tar.gz
cd gsl-1.16
./configure
make
sudo make install
Add these lines to your .bashrc file on your home directory.
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib
export CFLAGS="-I/usr/local/include"
export LDFLAGS="-L/usr/local/lib"
then, run source ~/.bashrc to set these environment variables.
It works fine when I change the version from the latest to the 1.6.
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/home/shg047/software/gsl/lib/
such as: to-mr: error while loading shared libraries: libgsl.so.19: cannot open shared object file: No such file or directory
Have you tried updating your library? The program I was trying to run simply needed a newer version of gsl (I had 1.9.5 while it needed 2.0.0 or newer).
If you are on arch you can run:
yaourt gsl
and select the appropriate one.
You can use gsl-config --libs in you makefile or in the command line when you link the gsl library. Just type gsl-config you can find the options it offers to you. Choose the options you need, you will find compile and link process much easier than before. As a result, when I type gsl-config --libs in my terminal, I get -L/usr/local/lib -lgsl -lgslcblas -lm. Although it is very simple, first you should know where you gsl is installed. You can add the directory to the PATH environment variable or use the absolute path to execute gsl-config .
I needed libgsl.so.19:
/snap/inkscape/current/bin/inkscape: error while loading shared libraries: libgsl.so.19: cannot open shared object file: No such file or directory
I solved it with:
Installing Anaconda
searched for libgsl.so.19 and found it in ~/anaconda3/lib
run LD_LIBRARY_PATH=$LD_LIBRARY_PATH:~/anaconda3/lib (best add it to ~/.basrc)
Recently, I try to create an makefile as below:
all:
g++ test.cpp -o Test
It creates an runnable Test. However, If I try to link it to an library (as LibCurl to use SSL connetion):
all:
g++ test.cpp -o Test -lcurl
It goes wrong (I already installed libcurl4-openssl-dev package as standard library)!
What does I miss? Can you give any solution? Thanks!!
Edit: The error is below:
fatal error: curl.h: No such file or directory
I guess, you need fix your sources:
#include <curl/curl.h>
The header files are missing in the include search path.
You will have install the development package of libcurl.
For example, install libcurl-devel-7.19.0-11.1.x86_64.rpm for Open Suse 11.1.
To know the list of files that would be installed by the rpm, download the rpm, type the following command in the downloaded dir.
rpm -qlp <rpmname>
As per the example above, the command would be
rpm -qlp libcurl-devel-7.19.0-11.1.x86_64.rpm
This will list the files along with the path in which it would be installed to.
In our example, the result would look like..
/usr/include/curl /usr/include/curl/curl.h /usr/include/curl/curlbuild.h
/usr/include/curl/curlrules.h
/usr/include/curl/curlver.h and so on...
and
Install the development libcurl package for the version of linux you use and include #include <curl/curl.h> in your code.
Refer http://curl.haxx.se/download.html to download the right one