I am using Codeblocks 13.12 on Ubuntu 14.04. While I am loading my shared library using dlopen, I got the error
dlopen failed: abc.so: cannot open shared object file: No such file or directory
Codeblocks "Build log" shows
Executing: xterm -T myConsoleApp -e /usr/bin/cb_console_runner LD_LIBRARY_PATH=$LD_LIBRARY_PATH:. /home/app/myConsoleApp
But my libs reside on ../libx64, so I must provide LD_LIBRARY_PATH=$LD_LIBRARY_PATH:../libx64 instead.
How can I do that using C::B 13.12?
Related
I encountered this problem when I compiled mosquitto on my Fedora 21 box from source.
mosquitto_pub: error while loading shared libraries:
libmosquitto.so.1: cannot open shared object file: No such file or
directory
The clients (i.e mosquitto_pub and mosquitto_sub) keep throwing that error even with reinstallation.
Assuming you have installed the libraries to /usr/local/lib, which is the default, the correct answer is to run /sbin/ldconfig as root/sudo.
On some systems you will need to add /usr/local/lib to the paths that ld caches, e.g.
echo /usr/local/lib > /etc/ld.so.conf.d/local.conf
I fixed this problem with sysmlinks
$vi /etc/ld.so.conf
include ld.so.conf.d/*.conf
include /usr/local/lib
/usr/lib
/usr/local/lib
$/sbin/ldconfig
$ln -s /usr/local/lib/libmosquitto.so.1 /usr/lib/libmosquitto.so.1
This indicates that the linker does not know where to find the library. Just run sudo /sbin/ldconfig to update the linker cache of libraries. This is not something that is unique to mosquitto.
I installed mosquitto from source on Ubuntu 20.04. So, the libmosquitto.so.1 was in the same directory as the source files. I copied it to usr/lib/x86_64-linux-gnufolder. Then running the mosquitto_sub worked!
The problem I faced has been solved here:
Loading shared library in open-mpi/ mpi-run
I know not how, setting LD_LIBRARY_PATH or specifying -x LD_LIBRARY_PATH fixes the problem, when my installation itself specifies the necessary -L arguments. My installation is in ~/mpi/
I have also included my compile-link configs.
$ mpic++ -showme:version
mpic++: Open MPI 1.6.3 (Language: C++)
$ mpic++ -showme
g++ -I/home/vigneshwaren/mpi/include -pthread -L/home/vigneshwaren/mpi/lib
-lmpi_cxx -lmpi -ldl -lm -Wl,--export-dynamic -lrt -lnsl -lutil -lm -ldl
$ mpic++ -showme:libdirs
/home/vigneshwaren/mpi/lib
$ mpic++ -showme:libs
mpi_cxx mpi dl m rt nsl util m dl % Notice mpi_cxx here %
When I compiled with mpic++ <file> and ran with mpirun a.out I got a (shared library) linker error
error while loading shared libraries: libmpi_cxx.so.1:
cannot open shared object file: No such file or directory
The error has been fixed by setting LD_LIBRARY_PATH. The question is how and why? What am i missing? Why is LD_LIBRARY_PATH required when my installation looks just fine.
libdl, libm, librt, libnsl and libutil are all essential system-wide libraries and they come as part of the very basic OS installation. libmpi and libmpi_cxx are part of the Open MPI installation and in your case are located in a non-standard location that must be explicitly included in the linker search path LD_LIBRARY_PATH.
It is possible to modify the configuration of the Open MPI compiler wrappers and make them pass the -rpath option to the linker. -rpath takes a library path and appends its to a list, stored inside the executable file, which tells the runtime link editor (a.k.a. the dynamic linker) where to search for libraries before it consults the LD_LIBRARY_PATH variable. For example, in your case the following option would suffice:
-Wl,-rpath,/home/vigneshwaren/mpi/lib
This would embed the path to the Open MPI libraries inside the executable and it would not matter if that path is part of LD_LIBRARY_PATH at run time or not.
To make the corresponding wrapper add that option to the list of compiler flags, you would have to modify the mpiXX-wrapper-data.txt file (where XX is cc, c++, CC, f90, etc.), located in mpi/share/openmpi/. For example, to make mpicc pass the option, you would have to modify /home/vigneshwaren/mpi/share/openmpi/mpicc-wrapper-data.txt and add the following to the line that starts with linker_flags=:
linker_flags= ... -Wl,-rpath,${prefix}/lib
${prefix} is automatically expanded by the wrapper to the current Open MPI installation path.
In my case, I just simply appends
export LD_LIBRARY_PATH=/PATH_TO_openmpi-version/lib:$LD_LIBRARY_PATH
For example
export LD_LIBRARY_PATH=/usr/local/openmpi-1.8.1/lib:$LD_LIBRARY_PATH
into $HOME/.bashrc file and then source it to active again source $HOME/.bashrc.
I installed mpich 3.2 using the following command on Ubuntu.
sudo apt-get install mpich
When I tried to run the mpi process using mpiexec, I got the same error.
/home/node1/examples/.libs/lt-cpi: error while loading shared libraries: libmpi.so.0: cannot open shared object file: No such file or directory
Configuring LD_LIBRARY_PATH didn't fix my problem.
I did a search for the file 'libmpi.so.0' on my machine but couldn't find it. Took me some time to figure out that 'libmpi.so.0' file is named as 'libmpi.so' on my machine. So I renamed it to 'libmpi.so.0'.
It solved my problem!
If you are having the same problem and you installed the library through apt-get, then do the following.
The file 'libmpi.so' should be in the location '/usr/lib/'. Rename the file to 'libmpi.so.0'
mv /usr/lib/libmpi.so /usr/lib/libmpi.so.0
After that MPI jobs should run without any problem.
If 'libmpi.so' is not found in '/usr/lib', you can get its location using the following command.
whereis libmpi.so
first, run this command
$ sudo apt-get install libcr-dev
if still have this problem then configure LD_LIBRARY_PATH like this:
export LD_LIBRARY_PATH=/usr/local/mpich-3.2.1/lib:$LD_LIBRARY_PATH
then add it to ~/.bashrc before this line:
[ -z "$PS1" ] && return
Simply running
$ ldconfig
appears to me as a better way to solve the problem (taken from a comment on this question). In particular, since it avoids misuse of the LD_LIBRARY_PATH environment variable. See here and here, for why I believe it's misused to solve the problem at hand.
I am using ft232r library provided by ftdi for programming an LPC11C14 micro-controller through Linux Mint. To initialize the software, I need to run the following command:
./ft232r_prog --manufacturer Sunswift --product $(PROJECT_NAME) --invert_rts --invert_dtr
When I run the code, I get the following issue:
Error while loading shared libraries: libftdi.so.1: cannot open shared object file: No such file or directory
on running ldd ft232r_prog, I get:
linux-gate.so.1 => (0xf77b8000)
libusb-0.1.so.4 => /lib/i386-linux-gnu/libusb-0.1.so.4 (0xf7790000)
libftdi.so.1 => not found
libc.so.6 => /lib/i386-linux-gnu/libc.so.6 (0xf75e5000)
/lib/ld-linux.so.2 (0xf77b9000)
The file libftdi.so.1 is located in /usr/lib/x86_64-linux-gnu. Since the executable ft232r_prog is unable to find the .so file, I have tried the following:
Updated the path environment variable to contain /usr/lib/x86_64-linux-gnu -- Failed
Updated the $LD_LIBRARY_PATH environment variable to contain /usr/lib/x86_64-linux-gnu -- Failed
Ran ldconfig in /usr/lib/x86_64-linux-gnu -- Failed
This appears to be a common issue with including shared libraries. Any ideas on how I can resolve it?
Thanks
To install 32-bit version of libftdi on Ubuntu 12.04 x64 try following:
$ sudo apt-get install libftdi1:i386
I suspect your system is 64-bit and the program is 32-bit. In this case, you need to install the 32-bit version of the library.
I am following the explanation in this page and this page trying to build and use shared libraries on Ubuntu Linux.
I am building the libraries and application using a cross-compiler on my PC, than copying the files to the target system and running there.
Finally, I am at the stage where all symlinks are defined correctly and the I am able to run the application - but not in the required form.
Let's say that I have a shared library libtest.so.1.0 in a directory /home/ysap/libs. I then created the symlinks libtest.so.1 and libtest.so in the same directory, both pointing to the library file.
In the directory /home/ysap/apps I have an application program app.e that uses the test library.
Now, to run the application, I can type:
> LD_LIBRARY_PATH=/home/ysap/libs ./app.e
and the application runs nicely. However, I'd like to eliminate the assignment, so I tried typing:
> export LD_LIBRARY_PATH=/home/ysap/libs
> ./app.e
but unfortunately I get an error message, saying:
./app.e: error while loading shared libraries: libtest.so.1: cannot open shared object file: No such file or directory
I also tried typing:
> ldconfig -n /home/ysap/libs
and
> sudo ldconfig -n /home/ysap/libs
but it does not help.
What am I doing wrong? How can I make app.e run w/o the variable assignment?
Update 1:
The application uses the mmap() call, so it has to be run with sudo priviledge. The actual invocation line is:
> sudo LD_LIBRARY_PATH=/home/ysap/libs ./app.e
Is it possible that the export-ed variable is not updated in the sudo environment?
Update 2:
Output of ldd ./app.e:
libtest.so.1 => /home/ysap/libs/libtest.so.1 (0xb6faa000)
libgcc_s.so.1 => /lib/arm-linux-gnueabi/libgcc_s.so.1 (0xb6f85000)
libc.so.6 => /lib/arm-linux-gnueabi/libc.so.6 (0xb6ea4000)
/lib/ld-linux.so.3 (0xb6fb7000)
The sudo problem is as #duskwuff states, but if you want to compile an application, and not need to modify the LD_LIBRARY_PATH variable, when linking the application you can use the $ORIGIN variable, which is recognized by most recent versions of linux.
If all the libraries are in the current directory, then when you link the application, you use the extra option:
-Wl,-R'$ORIGIN'
You need to quote the option to prevent it being expanded by the shell when compiling.
If you're putting it into a Makefile then you use:
-Wl,-R\$$ORIGIN
the $$ is for make to use a $, the \ is to prevent the shell that is invoked from the command line expanding the variable before passing it into the command.
You can use any symbolic path reference, so if you had a structure where binaries were in bin/ and libraries were in lib/, you can use $ORIGIN/../lib.
This works for dlopen as well, so it will find libraries when they are being dynamically loaded at run-time
Loading libraries from a user-specified path is a security risk, so sudo always strips out all LD_ environment variables, including LD_LIBRARY_PATH.
I am using gdbserver on target and CodeSourcery IDE. My hardware is a gumstix with a omap3530.
I can step through code in my main application but if I attempt to step into a function in a shared library I get memory address and a debugger terminates.
This is my library that is compiled and copied to the /lib folder on the target system.(it does have debug symbols) I have attempted to use the .gbdinit file to set solib-absolute-prefix /lib
Here are the warnings from the gdb trace:
903,056 13-gdb-set sysroot-on-target /lib
903,065 13^done
903,065 (gdb)
903,065 14-target-select remote 192.168.1.101:2345
903,114 =thread-group-started,id="i1",pid="42000"
903,114 =thread-created,id="1",group-id="i1"
903,115 15-list-thread-groups --available
903,120 16-list-thread-groups
903,128 &"warning: Unable to find dynamic linker breakpoint function.\nGDB will be unable to debug shared library initializers\nand track explicitly loaded dynamic code."
903,128 &"\n"
Which leads to
903,395 &"Error while mapping shared library sections:\n"
903,397 &"/lib/libCoreLib.so: Invalid argument.\n"
903,399 =library-loaded,id="/lib/libCoreLib.so",target-name="/lib/libCoreLib.so",hostname="/lib/libCoreLib.so",low-address="0x0",high-address="0x0",symbols-loaded="0",thread-group="i1"
You can debug with the library installed on your host, provided the debugging machine is also the development machine. In that case, you use set sysroot instead of set sysroot-on-target. For example :
set sysroot /home/username/.../rootfs/
where /home/username/.../rootfs/ contains a copy of your target filesystem
I think you should also specify / instead of /lib
Target with debug symbols
This is the simplest method to get working, and it is specially useful when you are developing one particular shared library.
First copy the test executable and shared library to the target with debug information:
check with readelf ----debug-dump=decodedline libmyib.so: How can I tell if a library was compiled with -g?
I recommend using an NFS server on host, so that the compiled output gets automatically uploaded after compilation
Then on target:
gdbserver --multi :1234 ./executable_name
Host:
arm-linux-gnueabihf-gdb -q -nh \
-ex "target extended-remote target-hostname-or-ip:1234" \
-ex "file ./executable_name" \
-ex 'tb main' \
-ex 'c' \
-ex 'set solib-search-path .'
sharedlibrary libmylib.so also works.
The problem I had was that gdbserver stops at the dynamic loader, before main, and the dynamic libraries are not yet loaded at that point, and so GDB does not know where the symbols will go in memory yet.
GDB appears to have some mechanisms to automatically load shared library symbols, and if I compile for host, and run gdbserver locally, running to main is not needed. But on the ARM target, that is the most reliable thing to do.
Target gdbserver 7.12-6, host arm-linux-gnueabihf-gdb 7.6.1 from Linaro.
Target libraries without debug symbols
It is common to strip target libraries before deployment on embedded targets, since debug information makes them way larger.
For example, Buildroot does that by default, but you can disable it with BR2_STRIP_none=y.
You can identify this scenario by running:
info shared
Which shows something like:
From To Syms Read Shared Object Library
0x00007ffff7df7f90 0x00007ffff7dfcdd7 Yes (*) target:/lib/ld64-uClibc.so.0
0x00007ffff7b3a9b0 0x00007ffff7bbe05d Yes (*) target:/lib/libc.so.0
(*): Shared library is missing debugging information.
so there are asterisks (*) for both of the libraries which says that debug information is missing.
If that is the case, then you have to tell GDB to use the shared libraries on host before they were stripped.
Buildroot for example makes that easy for us, as it maintains the staging directory which contains the shared libraries before they were stripped and in the same relative paths as in the target:
set sysroot buildroot/output/staging/
When this option is set, gdb immediately searches for libraries in the host instead of target, and finds /lib/libc.so.0 at the path buildroot/output/staging/ + /lib/libc.so.0:
Reading symbols from buildroot/output/staging/lib/ld64-uClibc.so.0...done.
Reading symbols from buildroot/output/staging/lib/libc.so.0...done.
TODO: I don't think you can set more than one sysroot, so all your shared libraries must be placed in their correct relative paths as in the target image.
If you check the bad default sysroot, you will see:
show sysroot
give:
target:
which means that gdb searches for shared libraries on the target root / by default.
Similar issue was encountered while debugging. The debug was hanging up. Configuration is as follows
Host: Ubuntu 12.04LTS
IDE: Eclipse Kepler
Target: Beaglebone Black / ARM A8
OS: Angstrom
Solution
Update libraries and includes
Select properties for project in Eclipse
C/C++ General > Paths and Symbols > (include TAB) GNU C > Add > Files
systems > / > usr Change from /usr/lib/gcc/i686-linux-gnu/4/6/include
to /usr/arm-linux-gnueabi/include
C/C++ General > Paths and Symbols > (Include TAB) GNU C++> Add >
Files systems > / > usr /usr/arm-linux-gnueabi/include/c++/4.6.3/arm-linux-gnueabi
C/C++ General > Paths and Symbols > (Library Paths TAB) > Add > Files
systems > / > usr /usr/arm-linux-gnueabi/lib
Good day,
If the 'debug-file-directory' variable in GDB is set incorrectly,
then the reported error messages contains:
warning: Unable to find dynamic linker breakpoint function.
The root filesystem of the target is located on my host PC at
/opt/arm-linux-gnueabihf-rootfs
The following two commands helped me to get remote debugging working
via gdbserver using GDB (v7.11.1):
set debug-file-directory /opt/arm-linux-gnueabihf-rootfs/usr/lib/debug
set sysroot /opt/arm-linux-gnueabihf-rootfs
I've noticed that if 'sysroot' has a trailing slash in the path,
then GDB fails to use it.You will see this (incorrect output) after connecting to the remote target:
Reading /lib/ld-linux-armhf.so.3 from remote target...
or
Reading symbols from /opt/arm-linux-gnueabihf-rootfs/lib/ld-linux-
armhf.so.3...(no debugging symbols found)...done
instead of the correct output:
Reading symbols from /opt/arm-linux-gnueabihf-rootfs/lib/ld-linux-
armhf.so.3...
Reading symbols from /opt/arm-linux-gnueabihf-rootfs/usr/lib/debug/
lib/arm-linux-gnueabihf/ld-2.23.so...done.
Regards,
Frikkie Thirion