问题描述
我正在使用一些我动态链接的poco库在Linux(Ubuntu 16.04)上准备一个c ++应用程序.我的项目文件夹包括:include,bin,lib,src和build文件夹以及相关的Makefile.到目前为止,我使用了以下Makefile,该文件是从/usr/local/lib
I'm preparing a c++ app on linux (Ubuntu 16.04) with the use of a few poco libraries which I have dynamically linked. I have project folder that consists of : include, bin, lib , src and build folders and the relevant Makefile. So far I used the following Makefile which got the libraries from /usr/local/lib
CC := g++
# Folders
SRCDIR := src
BUILDDIR := build
TARGETDIR := bin
# Targets
EXECUTABLE := C++_APP
TARGET := $(TARGETDIR)/$(EXECUTABLE)
SRCEXT := cpp
SOURCES := $(shell find $(SRCDIR) -type f -name *.$(SRCEXT))
OBJECTS := $(patsubst $(SRCDIR)/%,$(BUILDDIR)/%,$(SOURCES:.$(SRCEXT)=.o))
CFLAGS := -c -Wall
INC := -I include -I /usr/local/include
LIB := -L /usr/local/lib -lPocoFoundation -lPocoNet -lPocoUtil
$(TARGET): $(OBJECTS)
@echo " Linking..."
@echo " $(CC) $^ -o $(TARGET) $(LIB)"; $(CC) $^ -o $(TARGET) $(LIB)
$(BUILDDIR)/%.o: $(SRCDIR)/%.$(SRCEXT)
@mkdir -p $(BUILDDIR)
@echo " $(CC) $(CFLAGS) $(INC) -c -o $@ $<"; $(CC) $(CFLAGS) $(INC) -c -o $@ $<
clean:
@echo " Cleaning...";
@echo " $(RM) -r $(BUILDDIR) $(TARGET)"; $(RM) -r $(BUILDDIR) $(TARGET)
.PHONY: clean
现在,我希望在运行链接器期间仅在项目lib文件夹中搜索库,而无需更改LD_LIBRARY_PATH或编辑ld.so.conf.因此,我进行了搜索,发现可以通过链接器参数-Wl,rpath,$ ORIGIN来实现.所以我假设我需要添加以下语句
Now I'd like during running the linker to search for libraries only in project lib folder without changing LD_LIBRARY_PATH or editing ld.so.conf. So I searched and I found that this can be achieved by the linker argument -Wl,rpath,$ORIGIN. So I assume that I need to add the following statement
LDFLAGS := -Wl,-rpath,$ORIGIN/../lib
,然后更改LIB语句,如下所示:
and change the the LIB statement as following:
LIB := -L $ORIGIN/../lib -lPocoFoundation -lPocoNet -lPocoUtil
但是它仍然从默认目录(usr/local/lib)中获取库,因为我在项目lib文件夹中没有库的情况下对其进行了测试.我做错了什么?
However it still get the libraries from the default directory (usr/local/lib) , since I tested it with no library on the project lib folder. What have I done wrong?
推荐答案
不,您误会了.您需要将文字字符串$ORIGIN/../lib
作为参数传递给链接器. $ORIGIN
令牌在创建之后保留在您的程序中,并且当运行时链接程序开始运行您的程序时,它将用调用程序的当前路径替换$ORIGIN
.即使您已将程序复制到其他位置,也是如此.因此,如果您以/usr/local/bin/myprogram
身份运行程序,则运行时链接程序会将$ORIGIN
替换为/usr/local/bin
.如果将其复制到/opt/mystuff/libexec/myprogram
,则运行时链接程序会将$ORIGIN
替换为/opt/mystuff/libexec
.
No, you're misunderstanding. You need to pass the literal string $ORIGIN/../lib
as an argument to your linker. The $ORIGIN
token is kept inside your program after it's created and when the runtime linker starts to run your program it will replace $ORIGIN
with the current path that your program was invoked from. This is true even if you've copied your program somewhere else. So if you run your program as /usr/local/bin/myprogram
then the runtime linker will replace $ORIGIN
with /usr/local/bin
. If you copy it to /opt/mystuff/libexec/myprogram
then the runtime linker will replace $ORIGIN
with /opt/mystuff/libexec
.
为了将文字$
传递给make配方调用的命令,您必须通过将$
加倍来对其进行转义:$$
.否则,make将$
视为引入了make变量或函数.请记住,make变量避免使用括号等是完全合法的,如果 是单个字符(请注意,$@
,$<
等)
In order to pass a literal $
to the command invoked by a make recipe, you have to escape the $
by doubling it: $$
. Otherwise, make will see the $
as introducing a make variable or function. Remember, it's perfectly legal for a make variable to avoid the parentheses etc., if it's a single character (note, $@
, $<
, etc.)
因此,当您编写-Wl,-rpath,$ORIGIN/../lib
时,make会将$ORIGIN
中的$O
解释为扩展名为O
的变量,该变量为空,为您提供-Wl,-rpath,RIGIN/../lib
.
So when you write -Wl,-rpath,$ORIGIN/../lib
make will interpret the $O
in $ORIGIN
as expanding a variable named O
, which is empty, giving you -Wl,-rpath,RIGIN/../lib
.
此外,您还必须从外壳中转出$
,否则它将尝试将$ORIGIN
扩展为不需要的外壳变量.
Also you have to escape the $
from the shell, otherwise it will try to expand $ORIGIN
as a shell variable which you don't want.
您想做这样的事情:
LDFLAGS = '-Wl,-rpath,$$ORIGIN/../lib' -L/usr/local/lib
LDLIBS = -lPocoFoundation -lPocoNet -lPocoUtil
$(TARGET): $(OBJECTS)
@echo " Linking..."
$(CC) $^ -o $@ $(LDFLAGS) $(LDLIBS)
(我不知道您为什么使用@
隐藏命令,然后回显命令...为什么不只取出@
和echo
并让命令显示出来?)
(I don't know why you use @
to hide the command, then echo the command... why not just take out the @
and the echo
and let make show you the command?)
这篇关于如何在Makefile中正确包含-Wl,-rpath,$ ORIGIN链接器参数?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!