link error when compile a libevent based C code - http

Got a sample program (from https://raw.githubusercontent.com/libevent/libevent/master/sample/https-client.c) that uses libevent to simulate HTTPS client. I saved it to te1.c and compiled it, but got the following link error.
$ gcc -g te1.c -levent -levent_openssl
/tmp/cc5xxmcP.o: In function `http_request_done':
/home/jin1/tmp/te1.c:82: undefined reference to `evhttp_request_get_response_code_line'
/tmp/cc5xxmcP.o: In function `main':
/home/jin1/tmp/te1.c:297: undefined reference to `bufferevent_openssl_set_allow_dirty_shutdown'
/home/jin1/tmp/te1.c:301: undefined reference to `evhttp_connection_base_bufferevent_new'
collect2: ld returned 1 exit status
Any idea what library has the functions such as evhttp_request_get_response_code_line, evhttp_connection_base_bufferevent_new? Thanks in advance!

Turned out the libevent-2.0.so.5.1.4 is installed /usr/lib (by apt-get install libevent-dev). libevent-2.0.so.5.1.4 doesn't have the symbols. The latest libevent library that I compiled and installed were in /usr/local/bin.
The following line (with -L/usr/local/bin) helped:
gcc -g te1.c -L/usr/local/lib -levent -levent_openssl

Related

Connecting kdb+ to R

I'm trying to run a make file to install qserver on my OSX machine.
The make file gives me an error when I try to run. see code below:
make
/Library/Frameworks/R.framework/Resources/bin/R CMD gcc -g -O -fpic -m64 -shared -D KXVER=3 -I. -I/Library/Frameworks/R.framework/Resources/share/include base.c c.o -lpthread -L/Library/Frameworks/R.framework/Resources/share/lib -lR -o qserver.so
/Library/Frameworks/R.framework/Resources/bin/R: /Library/Frameworks/R.framework/Resources/bin/R: cannot execute binary file
make: *** [all] Error 126
Hoping someone can give me a pointer here on how to fix it.
Do you have the right version of gcc? I build with gcc-4.8 and have no issues. I recall a thread on the kdb list that mentioned the build required some features available only in later gcc versions. Give that a try.
[EDIT]
Nevermind, just saw that the error says the R binary was not found. Edit the make file to use the appropriate path for your R installation. If you don't have R installed, I suggest installing with homebrew:
brew tap homebrew/science
brew install r
After that you can replace the path in the Makefile as appropriate. I personally changed the Makefile to use $(shell R RHOME) to find the R home path, rather than assume a specific location.
JPC was partially right about gcc.
My system had two different versions of gcc loaded and the default was the standard one. I changed the makefile to run 'gcc-4.8'.
Once I finished that I got a new error: the make file couldn't locate my 'R.h' file...so i just had to reference where my r h-files were located....once I did that the make problem executed.

Cannot compile and link AVR program in OS X

I am working on a Mac with Yosemite OS X and I'm trying to compile a program in C that I could then upload onto my Arduino. I am following a tutorial.
I tried going through and reinstalling avr-gcc, but I got the same output. I tried searching for the file crtatmega328p.o on my system, but it is nowhere to be found and the same goes for the directory.
$ avr-gcc -Os -DF_CPU=16000000UL -mmcu=atmega328p -c -o Program.o Program.c
$ avr-gcc -mmcu=atmega328p Program.o -o Program
/usr/local/lib/gcc/avr/5.2.0/../../../../avr/bin/ld: cannot find crtatmega328p.o: No such file or directory
/usr/local/lib/gcc/avr/5.2.0/../../../../avr/bin/ld: cannot find -latmega328p
collect2: error: ld returned 1 exit status
I was just hit by this issue on GNU/Linux last week.
Actually, the compiler works fine. The cause of the issue is a failed linking attempt against avr-libc.
avr-libc-1.8.1 is simply too old to work with GCC 5. Although 1.8.1 is the latest version of avr-libc, but it was released one year ago... The developing version of avr-libc has updated to catch up GCC 5, you could clone the subversion repository:
svn co svn://svn.savannah.nongnu.org/avr-libc/trunk
and compile it by yourself. If you are not familiar about how to compile yourself home-made toolchains from the source code, there are plenty of documentation and tutorial on the web.

/usr/bin/ld: cannot find -lXmu

I want to install netgen and try to compile the source code.
During this I got the error message:
U -L/usr/lib/x86_64-linux-gnu -ltk8.6 -ltcl8.6 -lGL -lXmu -lX11 -fopenmp -Wl,-rpath -Wl,/opt/netgen/lib
/usr/bin/ld: cannot find -lXmu
collect2: error: ld returned 1 exit status
make[2]: *** [netgen] Error 1
Maybe I have to install an additional package?
Does anyone have an idea?
You can check, depending on your specific OS, if you are not missing the missing the non-versioned named (i.e. libXmu.so).
Check for ls /usr/lib/libXmu*.*, and if not found, type:
ln -s /usr/lib/libXmu.so libXmu.so.6
ln -s /usr/lib/libXuu.so libXmuu.so.1
If you don't have any libXmu*.* files, then you need to install first libxmu-dev:
sudo apt-get install libxmu-dev

"Unable to compile a JNI program" when installing rJava [duplicate]

I am not able to call rJava package in R 3.0. I got the following message
Error: package ‘rJava’ was built before R 3.0.0: please re-install it
I am getting error when I tried to re-install rJava package. I have provided the output of R CMD javareconf
Java interpreter : /usr/bin/java
Java version : 1.7.0_21
Java home path : /usr/lib/jvm/java-7-openjdk-i386/jre
Java compiler : /usr/lib/jvm/java-7-openjdk-i386/jre/../bin/javac
Java headers gen.: /usr/lib/jvm/java-7-openjdk-i386/jre/../bin/javah
Java archive tool: /usr/lib/jvm/java-7-openjdk-i386/jre/../bin/jar
trying to compile and link a JNI progam
detected JNI cpp flags :
detected JNI linker flags :
gcc -std=gnu99 -I/usr/share/R/include -DNDEBUG -fpic -O2 -pipe -g -c conftest.c -o conftest.o
conftest.c:1:17: fatal error: jni.h: No such file or directory
compilation terminated.
make: *** [conftest.o] Error 1
Unable to compile a JNI program
Java library path:
JNI cpp flags :
JNI linker flags :
Updating Java configuration in /usr/lib/R
Done.
I am using Ubuntu 13.04. I also tried apt-get install r-cran-rjava which is not helping to solve the issue. Regarding jni.h there were some solution here. But, not sure how can I use the solution here.
I ran into the exact same issue. My solution was to install the openjdk-7-* via
sudo apt-get install openjdk-7-*
Followed that with
sudo R CMD javareconf
and I was then able to install rJava in R via install.packages("rJava").
While perhaps not the most elegant solution it appears to have solved my problems with getting rJava to work.
For those getting the error:
error: unable to load shared object '/some/dir/rJava/libs/rJava.so': libjvm.so:
cannot open shared object file: No such file or directory
I solved the error locating the library in the system and linking them to /usr/lib:
$sudo updatedb
$locate libjvm.so
/usr/lib/debug/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/amd64/server/libjvm.so
/usr/lib/debug/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/amd64/zero/libjvm.so
/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/amd64/jamvm/libjvm.so
/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/amd64/server/libjvm.so
/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/amd64/zero/libjvm.so
$sudo ln -s /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/amd64/server/libjvm.so /usr/lib/
Installing rJava from the distribution packages as proposed in this askUbuntu answer also works:
sudo apt-get install r-cran-rjava
NOTE: tried from a Debian system.
I was also facing same error which was on RHEL8.1 & i resolved it as follows:
yum --enablerepo=* install java-1.8*
later i ran same command which was giving me error logs of R server.
R CMD javareconf
which turns into following output.

/usr/bin/ld: cannot find -lfreetype qt

Compiling on Fedora 10.
I am using qt for the first time. I started by creating a simple GUI application with all the default settings. When I tried to build the project I got the following error messages.
However, when I did a search for -lfreetype I found it in the following directory.
/usr/lib/libfreetype.so.6
/usr/lib/libfreetype.so.6.3.18
Is there anyway to resolve this issue?
Many thanks for any advice
Running build steps for project test1...
Creating gdb macros library...
Configuration unchanged, skipping QMake step.
Starting: /usr/bin/make debug -w
make: Entering directory `/home/steve/projects/qt/test1/test1'
/usr/bin/make -f Makefile.Debug
make[1]: Entering directory `/home/steve/projects/qt/test1/test1'
g++ -Wl,-rpath,/opt/qtsdk-2009.01/qt/lib -o test1 debug/main.o
debug/mainwindow.o debug/moc_mainwindow.o
-L/opt/qtsdk-2009.01/qt/lib
-lQtGui -L/opt/qtsdk-2009.01/qt/lib -L/usr/X11R6/lib
-pthread -lfreetype
-lgobject-2.0 -lSM -lICE -pthread -pthread
-lXrender -lfontconfig
-lXext -lX11 -lQtCore -lm -pthread -lgthread-2.0 -lrt
-lglib-2.0 -ldl -lpthread
/usr/bin/ld: cannot find -lfreetype
collect2: ld returned 1 exit status
make[1]: *** [test1] Error 1
make[1]: Leaving directory `/home/steve/projects/qt/test1/test1'
make: *** [debug] Error 2
make: Leaving directory `/home/steve/projects/qt/test1/test1'
Exited with code 2.
Error while building project test1
When executing build step 'Make'
You have to install the freetype-devel package. The devel package contains the header files which in the case of freetype shoud be located at: /usr/include/freetype.
I had the same problem on Ubuntu 8.10, QT 4.5. I "fixed" it with the following bizarre hack:
After the build fails, rename the QT lib directory to something else - e.g. "mv ../../qtsdk-2009.01/qt/lib ../../qtsdk-2009.01/qt/lib2"
Run "make" again, and it will fail again.
Restore the lib directory
Run "make" again, and now it works.
I have no idea why this happens.
Install freetype1-dev libgtk2.0-dev
and it will compile ok.
On Ubuntu 9.04, installing freetype1-dev & libgtk2.0-dev solves this problem.
But to surprise everyone the hack mentioned by Ross also works, I would really like to know how and why.. M looking into the source code of QTcreator to see if i can find out the reason why. If any one already know the reason, please let me know.
Thanks..
Just installed a newly fresh ubuntu 9.04 (dell D820)- installed qt creator nothing else - same problem
use option from S R that works because it needs libgtk2.0-dev (this will also load freetype6 ) installed from package manager.
Same effect you will see if you also install qt designer from package manager (it will install all the right packages
regards
Nico
I had same problems with Elive, freetype1-dev and libgtk2.0-dev and for the /usr/bin/ld: cannot find -lSM thing xorg-dev fixed the problem.
The first thing you have to make sure is that you have libfreetype.so installed in your computer. Use the command 'locate libfreetype.so', and you may find there is a '/usr/lib/libfreetype.so.6' in the result. The compile software can't identify libfreetype.so.6 as a shared library, so, you have to make a symbolic link to the target. Use the command 'ln -s /usr/lib/libfreetype.so.6 /usr/lib/libfreetype.so', when you compile the program again, you will find the error had gone. You can also solve the errors likely. Good Luck!

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