Linux 为什么每次运行应用程序时都必须使用导出定义 LD_LIBRARY_PATH？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/695530/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Why do I have to define LD_LIBRARY_PATH with an export every time I run my application?
提问by Paul Wicks
I have some code that uses some shared libraries (c code on gcc). When compiling I have to explicitly define the include and library directories using -I and -L, since they aren't in the standard places. When I try to run the code, I get the following error:
我有一些代码使用了一些共享库（gcc 上的 c 代码）。编译时，我必须使用 -I 和 -L 显式定义包含和库目录，因为它们不在标准位置。当我尝试运行代码时，出现以下错误：
./sync_test
./sync_test: error while loading shared libraries: libsync.so: cannot open shared object file: No such file or directory
However, do the following, everything works just fine:
但是，执行以下操作，一切正常：
export LD_LIBRARY_PATH="/path/to/library/"
./sync_test
Now, the strange part is, this only works once. If I try and run sync_test again I get the same error unless I run the export command first. I tried adding the following to my .bashrc, but it made no difference:
现在，奇怪的是，这只起作用一次。如果我再次尝试运行 sync_test，除非我先运行 export 命令，否则我会得到同样的错误。我尝试将以下内容添加到我的 .bashrc 中，但没有任何区别：
LD_LIBRARY_PATH="/path/to/library/"
采纳答案by brian-brazil
Use
用
export LD_LIBRARY_PATH="/path/to/library/"
in your .bashrc otherwise, it'll only be available to bash and not any programs you start.
否则，在您的 .bashrc 中，它只能用于 bash 而不能用于您启动的任何程序。
Try -R/path/to/library/flag when you're linking, it'll make the program look in that directory and you won't need to set any environment variables.
-R/path/to/library/链接时尝试标志，它会使程序在该目录中查找，并且您不需要设置任何环境变量。
EDIT: Looks like -Ris Solaris only, and you're on Linux.
编辑：看起来-R仅适用于 Solaris，而您使用的是 Linux。
An alternate way would be to add the path to /etc/ld.so.confand run ldconfig. Note that this is a global change that will apply to all dynamically linked binaries.
另一种方法是添加路径/etc/ld.so.conf并运行ldconfig. 请注意，这是一个全局更改，将应用于所有动态链接的二进制文件。
回答by bedwyr
Did you 'export' in your .bashrc?
您在 .bashrc 中“导出”了吗？
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:"/path/to/library"
回答by brian-brazil
You can just put this all on one line:
你可以把这一切放在一行上：
LD_LIBRARY_PATH="$LD_LIBRARY_PATH:/path/to/library" ./sync_test
Should make things a little easier, even if it doesn't change anything fundamental
应该让事情变得更容易一些，即使它不会改变任何基本的东西
回答by sigjuice
You should avoid setting LD_LIBRARY_PATHin your .bashrc. See "Why LD_LIBRARY_PATH is bad"for more information.
你应该避免LD_LIBRARY_PATH在你的.bashrc. 有关详细信息，请参阅“ Why LD_LIBRARY_PATH is bad”。
Use the linker option -rpathwhile linking so that the dynamic linker knows where to find libsync.soduring runtime.
链接时使用链接器选项-rpath以便动态链接器知道libsync.so在运行时在哪里找到。
gcc ... -Wl,-rpath /path/to/library -L/path/to/library -lsync -o sync_test
EDIT:
编辑：
Another way would be to use a wrapper like this
另一种方法是使用这样的包装器
#!/bin/bash
LD_LIBRARY_PATH=/path/to/library sync_test "$@"
If sync_teststarts any other programs, they might end up using the libs in /path/to/librarywhich may or may not be intended.
如果sync_test启动任何其他程序，它们最终可能会使用/path/to/library可能或可能不打算使用的库。
回答by Roalt
What you also can do, if it's something you installed on your system, is to add the directory that contains the shared libraries to your /etc/ld.so.conffile, or make a new file in /etc/ld.so.conf.d/
您还可以做的是，如果它是您在系统上安装的东西，则是将包含共享库的目录添加到您的/etc/ld.so.conf文件中，或者在/etc/ld.so 中创建一个新文件。配置文件/
(I've both checked RHEL5 and Ubuntu distribution so I think it's generic for linux)
（我已经检查了 RHEL5 和 Ubuntu 发行版，所以我认为它适用于 linux）
The ldconfig program will make sure they are system-wide included.
ldconfig 程序将确保它们包含在系统范围内。
See the following link for more information: www.dwheeler.com/secure-programs/Secure-Programs-HOWTO/dlls.html
有关更多信息，请参阅以下链接： www.dwheeler.com/secure-programs/Secure-Programs-HOWTO/dlls.html
回答by fgp
Instead of overriding the library search path at runtime with LD_LIBRARY_PATH, you could instead bake it into the binary itself with rpath. If you link with GCC adding -Wl,-rpath,<libdir>should do the trick, if you link with ld it's just -rpath <libdir>.
与其在运行时使用 LD_LIBRARY_PATH 覆盖库搜索路径，您还可以使用rpath. 如果您使用 GCC 添加链接-Wl,-rpath,<libdir>应该可以解决问题，如果您使用 ld 链接它只是-rpath <libdir>.
回答by user3916212
You could add in your code a call system with the new definition:
您可以在代码中添加具有新定义的调用系统：
sprintf(newdef,"export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:%s:%s",ld1,ld2);
system(newdef);
But, I don't know it that is the rigth solution but it works.
但是，我不知道这是正确的解决方案，但它有效。
Regards
问候
