g++找不到已安装的库

Question

我正在尝试编译需要所需库 libmusicxml 的示例文件。

我按照他们所说的编译了库（cmake、make、make install），它制作并安装了一堆文件：

Install the project...
-- Install configuration: ""
-- Installing: /usr/local/lib/libmusicxml2.so.3.00
-- Installing: /usr/local/lib/libmusicxml2.so
-- Installing: /usr/local/include/libmusicxml/musicxmlfactory.h
-- Installing: /usr/local/include/libmusicxml/sortvisitor.h
-- Installing: /usr/local/include/libmusicxml/xmlreader.h
... etc

现在我想编译他们的一个示例文件，所以我运行 g+ filename.cpp，它给了我以下错误：

libmusicxml.h: No such file or directory

这是否意味着它没有在 /usr/local 中看到该库？我可以在某处指定这个吗？设置路径什么的？

我已经确保从here 获得最新版本的 libmusicxml 库，并且做了同样的事情（cmake 后跟 make）。

当我查看给定示例并尝试制作一个（使用提供的 make 文件，根据开发人员的说法）时，它不想这样做：

dorien@XP:~/bin/libmusicxml-master/samples$ make
gcc -g -O3 -Wall -Wuninitialized -I../src/elements -I../src/interface -I../src/files -I../src/lib -I../src/parser -I../src/visitors -I../src/guido -I../src/operations countnotes.cpp ../libmusicxml2.a -lstdc++ -o countnotes
gcc: error: ../libmusicxml2.a: No such file or directory
Makefile:14: recipe for target 'countnotes' failed

-> 我试图找到 libmusicxml2.a，但它似乎不存在。

当我运行 xml2guido（在包的根目录中似乎有一个编译版本）时，我得到：

xml2guido: error while loading shared libraries: libmusicxml2.so.3.00: cannot open shared object file: No such file or directory

不过同目录下还有一个libmusicxml2.so.3.00

可能是包没有正确链接？或者关于丢失的 .a 文件？

我确实认为它是正确构建的：

 make
[ 73%] Built target musicxml2
[ 75%] Built target RandomMusic
[ 78%] Built target countnotes
[ 80%] Built target partsummary
[ 82%] Built target readunrolled
[ 85%] Built target xml2guido
[ 87%] Built target xml2midi
[ 90%] Built target xmlclone
[ 92%] Built target xmlfactory
[ 95%] Built target xmliter
[ 97%] Built target xmlread
[100%] Built target xmltranspose

dorien@XP:~/bin/libmusicxml-master$ sudo make install
[ 73%] Built target musicxml2
[ 75%] Built target RandomMusic
[ 78%] Built target countnotes
[ 80%] Built target partsummary
[ 82%] Built target readunrolled
[ 85%] Built target xml2guido
[ 87%] Built target xml2midi
[ 90%] Built target xmlclone
[ 92%] Built target xmlfactory
[ 95%] Built target xmliter
[ 97%] Built target xmlread
[100%] Built target xmltranspose
Install the project...
-- Install configuration: ""
-- Up-to-date: /usr/local/lib/libmusicxml2.so.3.00
-- Up-to-date: /usr/local/lib/libmusicxml2.so
-- Up-to-date: /usr/local/include/libmusicxml/musicxmlfactory.h
-- Up-to-date: /usr/local/include/libmusicxml/sortvisitor.h
-- Up-to-date: /usr/local/include/libmusicxml/xmlreader.h
-- Up-to-date: /usr/local/include/libmusicxml/xmlfile.h
-- Up-to-date: /usr/local/include/libmusicxml/libmusicxml.h
-- Up-to-date: /usr/local/include/libmusicxml/unrolled_xml_tree_browser.h
-- Up-to-date: /usr/local/include/libmusicxml/xml.h
-- Up-to-date: /usr/local/include/libmusicxml/elements.h
-- Up-to-date: /usr/local/include/libmusicxml/factory.h
-- Up-to-date: /usr/local/include/libmusicxml/types.h
-- Up-to-date: /usr/local/include/libmusicxml/typedefs.h
-- Up-to-date: /usr/local/include/libmusicxml/xml_tree_browser.h
-- Up-to-date: /usr/local/include/libmusicxml/versions.h
-- Up-to-date: /usr/local/include/libmusicxml/exports.h

Answer 1

在我运行之前无法识别库（和标题）：

export LD_LIBRARY_PATH=/addressto/libmusicxml-master

这解决了它。

Answer 2

这是否意味着它没有在 /usr/local 中看到该库？

这意味着它没有找到标题libmusicxml.h。您没有告诉编译器在 /usr/local/include/libmusicxml 中查找它。

我可以在某处指定吗？设置路径还是什么？

查看编译器的文档。在 gcc 中，包含搜索路径的选项是 -I。

我建议不要从/usr/local/include/libmusicxml/ 中搜索标题libmusicxml.h，而是包含libmusicxml/libmusicxml.h 并从/usr/local/include 中搜索。这会更简单，因为 g++ 默认从 /usr/local/include 搜索，因此不需要编译器选项。