I need link cURL in Ubuntu 11.04 after installed cURL by source code.
# curl-config --libs
# curl-config --cflags
# Testing cURL
# C++ Compiler (Default: g++)
CXX = g++
CFLAGS = -Wall -Werror
INCLUDE = -Iusr/local/include
LDFLAGS = -Lusr/local/lib
LDLIBS = -lcurl
SOURCES = src/main.cpp
OUT = test
$(CXX) -o $(OUT) $(INCLUDE) $(CFLAGS) $(LDFLAGS) $(SOURCES)
int main( void )
curl = curl_easy_init();
curl_easy_setopt(curl, CURLOPT_URL, "http://example.com");
res = curl_easy_perform(curl);
g++ -o test -Iusr/local/include -Wall -Werror -Lusr/local/lib src/main.cpp
/tmp/ccli90i2.o: In function `main':
main.cpp:(.text+0xa): undefined reference to `curl_easy_init'
main.cpp:(.text+0x31): undefined reference to `curl_easy_setopt'
main.cpp:(.text+0x3d): undefined reference to `curl_easy_perform'
main.cpp:(.text+0x4d): undefined reference to `curl_easy_cleanup'
collect2: ld returned 1 exit status
make: ** [build] Erro 1
This should do the job. You didn't really link to cURL before.
build: $(SOURCES) $(CXX) -o $(OUT) $(INCLUDE) $(CFLAGS) $(LDFLAGS) $(LDLIBS) $(SOURCES)
Notice the added
Oh, I should add that basically what happens is that you throw overboard the built-in rules of GNU make (see output of
make -np) and define your own. I would suggest that you either use the built-in ones if you want to rely on the respective variables to be sufficient to control the build or that you still split it up into compilation and link step for the sake of brevity.
Brief explanation: GNU make comes with a rule that states how to make a
.o file from a
.c) file. So your make file could perhaps be rewritten to (approx.)
# Testing cURL # MAKEFILE # C++ Compiler (Default: g++) CXX = g++ CFLAGS = -Wall -Werror # Librarys INCLUDE = -I/usr/local/include LDFLAGS = -L/usr/local/lib LDLIBS = -lcurl # Details SOURCES = src/main.cpp OUT = test .PHONY: all all: build $(OUT): $(patsubst %.cpp,%.o,$(SOURCES))
This should generate the binary with the name
test (contents of
OUT) and makes otherwise use of the built-in rules. Make infers from the use of
.o files that there must be source files, will look for them and compile them. So implicitly this build will run one invocation for each
.cpp file and one for the linking step.