I am going to write a Hello World module in Ubuntu 10.10 (with the kernel 2.6.35-28-generic). Headers are located:
/usr/src/linux-headers-2.6.35-28-generic
hello.c:
#include <linux/kernel.h>
#include <linux/module.h>
int init_module(void)
{
printk("Hello, world\n");
return 0;
}
void cleanup_module(void)
{
printk("Goodbye\n");
}
and Makefile:
CC = gcc
CFLAGS = -Wall -DMODULE -D__KERNEL__
hello.o: hello.c
$(CC) $(CFLAGS) -c hello.c
echo insmod hello.o to install
echo rmmod to delete
There is an error while make:
hello.c:1: fatal error: linux/kernel.h : No such file or directory
compilation terminated.
How do I solve this?
You can't just use a traditional-style Makefile with Linux kernel modules; while you might be able to force something to work, it'll be a painful experience.
Start by reading the Documentation/kbuild/modules.txt file; it'll describe exactly what you need to do when writing a module Makefile so that it can hook neatly into the kernel's Kbuild environment. Your Makefile will probably look something like this:
ifneq ($(KERNELRELEASE),)
# kbuild part of makefile
obj-m := 8123.o
8123-y := 8123_if.o 8123_pci.o 8123_bin.o
else
# normal makefile
KDIR ?= /lib/modules/`uname -r`/build
default:
$(MAKE) -C $(KDIR) M=$$PWD
# Module specific targets
genbin:
echo "X" > 8123_bin.o_shipped
endif
Please trust me on this; while you might think you're "just one small change" from getting your own Makefile to work, even minor changes in kernel version will completely destroy your build all over again. Just take the hour now to write a Kbuild-compatible Makefile for your module. I wasted weeks of my life trying to maintain a pre-existing Makefile when the Kbuild infrastructure was introduced. Every new kernel caused me to lose hours of productivity.
For me this file ("linux/kernel.h") is in the package linux-libc-dev (Kubuntu 10.10).
Do you have /usr/src/linux symbolic link to your /usr/src/linux-headers-2.6.35-28-generic ?
If not then create one using following commands
# cd /usr/src
# ln -sfn linux-headers-2.6.35-28-generic linux
just as what #sarnold said , you should use the different Makefile.Just as following:
obj-m += hello.o
all:
make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
and use the command:
insmod hello.ko
to install this module.
Related
If I write this code and saved as a.cpp at ~/Desktop
#include <memory>
int main(){}
then input to bash:
cd /usr/bin
g++ -g ~/Desktop/a.cpp -o ~/Desktop/a
then the g++ will output plenty of messy code of errors.
I have found the reason is because it don't have authority to link XX.so library.
But if I add a 'sudo' , or set CWD to the path owned by user, g++ will work properly, as follows:
sudo g++ -g ~/Desktop/a.cpp -o ~/Desktop/a
or
cd ~/Desktop
g++ -g ~/Desktop/a.cpp -o ~/Desktop/a
Why do this happen? or how can I fix this?
You don't want to generate code directly in /usr/bin.
You generate your code in your user folder, maybe create a sub-directory called cppwork or something like that.
cd
mkdir cppwork
cd cppwork
g++ -g a.cpp -o a
Once you compiled in your directory, then you copy the file using install which will also take care of stripping the debug if any (i.e. the -g says to keep debug info—stripping is not mandatory).
sudo install -s a /usr/bin/a
As you can see, the place where I use sudo is with the install command.
That being said, I never use those directly. Now a day, I use cmake which means everything works automatically. But that would be a different discussion.
Thanks for every one. I have found the reason. It's because there is an executable program named 'array' in /usr/bin. And when CWD is /usr/bin, the compiler regard this 'array' as the c++ header <array>, so compiling error.
Then I need to find out why the compiler includes /usr/bin by mistake.
I am trying to compile a simple PJSIP program with Yocto/Openembedded. And I have this error : fatal error: pjsua-lib/pjsua.h: No such file or directoryHere is my Makefile:
all: simple_pjsua
simple_pjsua: simple_pjsua.c
$(CC) -o $# $< `pkg-config --cflags --libs libpjproject`
clean:
rm -f simple_pjsua.o simple_pjsua
And here is my simplepjsua_2.6.bb:
DESCRIPTION = "Open source SIP stack and media stack for presence, im/instant \
messaging, and multimedia communication"
SECTION = "libs"
HOMEPAGE = "http://www.pjsip.org/"
# there are various 3rd party sources which may or may not be part of the
# build, there license term vary or are not explicitely specified.
LICENSE = "CLOSED"
PR = "r0"
SRC_URI = "file://simple_pjsua.c \
file://Makefile \
file://README.txt"
S = "${WORKDIR}/"
do_compile() {
cd ${S}
#to prevent libpjproject.PC not found error
export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig
oe_runmake
}
do_install() {
install -m 0755 -d ${D}${bindir} ${D}${docdir}/simple_pjsua
install -m 0755 ${S}/simple_pjsua ${D}${bindir}
install -m 0755 ${WORKDIR}/README.txt ${D}${docdir}/simple_pjsua
}
I tried adding INC=-I/usr/include/pjsua-lib/ in the Makefile but nothing changed.. And if I want to compile it on my computer with make it's working.
What can I do?
EDIT :
I tried adding export LD_LIBRARY_PATH=/usr/include in do_compile() in the bb file. Same issue
You're linking against host libraries which really isn't the right thing to do unless you're building a native package (which you are not).
You need to make a recipe for pjsip to build and install that, and then this recipe should DEPEND on that.
make sure that /usr/include/pjsua-lib/pjsua.h file exist.
# INC=-I/usr/include/pjsua-lib # not ok
INC=-I/usr/include
i have started a project in C++ and need to implement some openssl libraries. I downloaded the libraries, followed the directions on how to install openssl.
it was a pain and had to install / reinstall multiple times for multiple reasons.
im finally able to seemingly correctly install openssl and compile the libraries, link them with -libcrypto and -libssl instead of the -lcrypto and -lssl i saw everywhere.
I have been through the process of debugging, my includes are fine and the implimentation seems to work because g++ find the error file and throws the compilation errors, but when it "Succesfully" compiles and i run the .exe i get this error.
I have searched my openssl intall location and i did find that file.
Here is my makefile code, all those location are clearly in the building path
# *- Makefile -*
compiler=g++
standLib=-lstdc++ -llibcrypto -llibssl
include=-I C:\openssl-1.1.0e\include
ExtLibrary=-L C:\openssl-1.1.0e // <--- LOCATION OF THE .dll FILE
outfile=-o main.exe
all : main.o fileReader.o main
clean :
del *.o *.exe
main: main.o fileReader.o numbers.o
$(compiler) main.o $(standLib) $(include) $(ExtLibrary) $(outfile)
main.o : main.cpp fileReader.cpp
$(compiler) -c main.cpp $(standLib) $(include) $(ExtLibrary)
fileReader.o : fileReader.cpp fileReader.h
$(compiler) -c fileReader.cpp $(standLib)
numbers.o : numbers.cpp numbers.h
$(compiler) -c numbers.cpp $(standlib)
What am i missing ? Thanks for any input or help !
** UPDATE **
i found that i can execute my program fine as long as its running in the same directory as openssl where the libcrypto-1_1-x64.dll is located.
How can i build my program so that it can run it on its own without openssl installed on the computer ? IE: if i want to give it to a friend who doesnt have openssl installed on his machine.
To solve this issue you should just add openssl's /bin directory to your path (using environment variables).
Uninstall & Reinstall mosquitto
copy both libcrypto.dll & libssl.dll files into mosquitto directory and reinstall mosquitto
Run mosquitto in cmd prompt:
cd C:\Program Files (x86)\mosquitto
mosquitto
Execute this sub command: mosquitto_sub -h test.mosquitto.org -t "#" -v
You should see messages coming from mosquitto.org test server
Gooday everyone
I'm fairly new to ubuntu C programing although I'm
rather experienced in C programing in windows.
I have recently come accross a number of codes written
in 2005 which I'm interested in learning how they work.
Those codes needs BOOST library to compile, however they won't
compile on the newest BOOST version present on my ubuntu 12.04.
I set the gcc compiler on lenient so that it ignores all those error
messages. The code did compile and ran afterwards.
However, when I used GDB debugger to watch how the program flows
I noticed that there are likely errors in the way the program runs
due to using a different BOOST version rather than it's original. Hence
I like to install the BOOST version corresponding to the code I downloaded.
To do that, I installed Ubuntu 5.04 and BOOST 1.33.0 which seemed to have been created in late 2005. I downloaded it
but I didnt found any detailed instruction on how to install it.
Only vague description on using BOOST jam, I played around with BOOST
jam for quite awhile without success.
And this old BOOST does not have installation commands like
"sudo apt-install boost-dev" style option
Thus I like to ask if anyone can give a easy to understand step by step instruction
on how to install the BOOST library downloaded from the above link.
like.....
step1: download boost jam from boost webpage
step2: unpack it in home/boost/ then type make configure
...and so on...
Big thanks for any useful info.
New Contents appended here
in response to the comments given
Hi, I went through the info given by your link and
managed to run the boost library examples given by your link.
That is, I can compile a single cpp file with the command
g++ -I boost_1_33_0 test.cpp -o test
(I'm keeping the boost library and the cpp file to be compiled in the
same folder)
However, the program package I'm interested in is build with make (not cmake).
I have some experience writting cmake files but not make files.
And I do not see any link to boost library command in the make file of the
program package. The readme file only has one sentence that says I
need to have boost installed without explaining what that meant.
I assume it means that either I have to build and do makeinstall the boost or
I could add some lines in the makefile for a link. I thought
maybe you can quickly point out whats missing in the makefile.
The readme file:
To compile, go into the moses directory and do 'make'. You'll need the
latest boost libraries. If compilation still fails for weird reasons,
you could try g++ with the -fpermissive (newer versions reject lots of
code that was ok with older ones). If you are going to be making
changes and recompiling frequently you'll probably want to disable -O3
in the makefile (I use templates liberally, so -O3 really speeds up
the code, but really slows down compilation).
And the makefile:
CC = g++
PROJ_NAME = moses
LINK_FLAGS = -Wall -Iutils/ -Itrees/ -Irewrite -I./ -Imodeling/ -Ifitness/ \
-Ialignment/ -Isim/ -Ilocal/ -O3
COMP_FLAGS = -Wall -Wno-sign-compare -Iutils/ -Itrees/ -Irewrite -I./ \
-Imodeling/ -Ifitness/ -Ialignment/ -Isim/ -Ilocal/ -O3
src := $(wildcard *.cc) $(wildcard utils/*.cc) $(wildcard trees/*.cc) $(wildcard modeling/*.cc) $(wildcard fitness/*.cc) $(wildcard alignment/*.cc) $(wildcard main/*.cc) $(wildcard rewrite/*.cc) $(wildcard sim/*.cc) $(wildcard local/*.cc)
obj := $(patsubst %.cc,%.o,$(src))
all: $(PROJ_NAME)
%.o: %.cc
$(CC) $(COMP_FLAGS) $< -c -o $#
$(PROJ_NAME): $(obj)
$(CC) $(LINK_FLAGS) $^ -o $(PROJ_NAME)
run:
$(PROJ_NAME)
clean:
find -regex ".*~\|.*\.o"|xargs rm -f
rm -f $(PROJ_NAME)
rm -f $(PROJ_NAME).exe*
depend:
makedepend -Y -- $(COMP_FLAGS) -- $(src)
utils/exceptions.o: utils/exceptions.h utils/utils.h
utils/io_util.o: utils/io_util.h utils/tree.h utils/basic_types.h
# ......lots more lines like that.........
I have an old instruction flying around here for Boost 1.34.1, which reads like this (project-specific stuff cut away):
unpack boost sources
cd into tools/jam/src
run ./build.sh to build bjam
cd into the main source directory
tools/jam/src/bin.linux/bjam threading=multi --layout=system --toolset=gcc --without-python variant=release --prefix=/usr/local install
The --without-python was necessary as the target system didn't have Python installed, which caused the build to fail messily.
Obviously you can / need to fiddle with the individual settings (like threading support, release vs. debug variant) to suit your needs, but it should be a good starting point.
If you need ICU support (for Boost.Regex and Boost.Locale), it gets more complicated...
Note that the build process has changed over the years; you shouldn't use the same procedure for more up-to-date boost versions. It's just what I used back then.
Edit:
As for the second part of your question, the Makefile doesn't need to refer to Boost explicitly if boost is installed in the standard system directories.
You do not have to state -I /usr/include for compilation as that is searched automatically; the same goes for -L /usr/lib during linkage.
The fact that the author of the Makefile copied the compiler flags into the linker flags verbatim doesn't really help intuitivity either... ;-)
If you have Boost in a custom directory (either the headers only, or by stating a custom directory in the --prefix option of my build instructions), you need to make the following modifications (look for "boost"):
LINK_FLAGS = -Wall -Iutils/ -Itrees/ -Irewrite -I./ -Imodeling/ -Ifitness/ \
-Ialignment/ -Isim/ -Ilocal/ -L /path/to/boost/libs -O3
COMP_FLAGS = -Wall -Wno-sign-compare -Iutils/ -Itrees/ -Irewrite -I./ \
-Imodeling/ -Ifitness/ -Ialignment/ -Isim/ -Ilocal/ \
-I /path/to/boost/includes -O3
That should do the trick. As the Makefile does not link any of the Boost binaries (e.g. -l boost_program_options or somesuch), it seems that it makes use of the Boost headers only, which would make the -L /path/to/boost/libs part (and, actually, the whole compilation step detailed above) superfluous. You should be able to get away with simply unpacking the sources and giving the header directory as additional include directory using -I /path/to/boost/headers.
I'm a newbie to g test and Here is what I am trying to do (On a Linux server from console):
1) Create a small project in C++ ( with a header file containing a function prototype, a cpp file with a function in it and another cpp file with main calling the function already defined in the header file )
2) Configure g test to write unit tests and test the function created in the step 1
3) Create another small project with a couple of unit tests (different scenarios to test the function created under the project in step 1)
Can anyone please tell how to configure g test and the projects created with an example?
Thanks in advance
First of all, get the most updated version of GoogleTest from the Subversion repository (you need Subversion installed):
cd ~
svn checkout http://googletest.googlecode.com/svn/trunk/ googletest-read-only
Then, build the library (you need cmake installed):
mv googletest-read-only googletest
mkdir googletest/lib
cd googletest/lib
cmake ..
make
At this point:
compiled libraries are in the ~/googletest/lib directory
include files are in the ~/googletest/include directory
To use googletest:
Include the header in your files:
#include "gtest/gtest.h"
Export the library path:
export GOOGLETESTDIR=~/googletest
Compile with
g++ ... -I$GOOGLETESTDIR/include -L$GOOGLETESTDIR/lib -lgtest -lpthread
Please find the tutorial
# http://www.yolinux.com/TUTORIALS/Cpp-GoogleTest.html
Caution!!
one correction at the makefile (test/src/Makefile). The order of the library path is not correct!!.
It would be like:
CXX = g++
CXXFLAGS = -g -L/opt/gtest/lib -lgtest -lgtest_main -lpthread
INCS = -I./ -I../../src -I/opt/gtest/include
OBJS = ../../src/Addition.o Addition_Test.o ../../src/Multiply.o Multiply_Test.o
testAll: $(OBJS)
$(CXX) $(INCS) -o testAll Main_TestAll.cpp $(OBJS) $(CXXFLAGS)
.cpp.o:
$(CXX) $(CXXFLAGS) -c $< -o $# $(INCS)
clean:
rm testAll *.o testAll.xml
After a small research here is what I found out:
If your project library contains files like:
1) callMain.cpp which calls the function to do some operations
2) reverse.cpp which contains the logic of reversing a number and
3) header.h containing the declaration of function prototypes
And if you have unit test case scenario scripts like unitTest1.cpp and unitTest2.cpp to be tested via gtest then, this can be achieved as follows:
g++ -I<gtest include directory location> -L<gtest directory location> <gtest_main.cc location> reverse.cpp unitTest1.cpp unitTest2.cpp -lgtest -lpthread -o test_try
This compiles and produces an executable like test_try which when executed gives the desired result. Please correct me if I'm wrong anywhere. Happy coding :)
New answer
Today I read the Google Test FAQ. It's not recommend to install a pre-compiled copy of Google Test(for example, into /usr/local). You can find the answer in the FAQ.
So, recommend this answer and this blog article.
Old answer
Following the CMake document of FindGTest.
The code below works for me.
cmake_minimum_required(VERSION 2.8)
################################
# Add gtest environment
################################
enable_testing()
find_package(GTest REQUIRED)
# add gtest include directory: way 1
include_directories(${GTest_INCLUDE_DIRS})
# add gtest include directory: way 2
#include_directories(${GTest_SOURCE_DIRS}/include ${GTest_SOURCE_DIR})
################################
# Build tests
################################
aux_source_directory(. DIR_SRCS)
add_executable(fooTest ${DIR_SRCS})
# parameter `gtest` should at the front of `pthread`
target_link_libraries(fooTest gtest pthread)
# Take all gtest cases as one Cmake test case
add_test(AllFooTest fooTest)
And then, you can using command:
cmake ., generate Makefile
make, build gtest routine
./fooTest, run gtest routine
make test, run cmake test, it's another way you can run the gtest