为什么 ld 无法从 /etc/ld.so.conf 的路径中找到库？

Question

我想将/opt/vertica/lib64 添加到系统库路径中，所以我执行以下步骤：
(1) 将/opt/vertica/lib64 添加到/etc/ld.so.conf，然后运行ldconfig，
(2) 检查：

 bash# ldconfig -p | grep vertica
    libverticaodbc.so (libc6,x86-64) => /opt/vertica/lib64/libverticaodbc.so
    ......

但是当我运行“ld -lverticaodbc --verbose”命令时：

==================================================
attempt to open /usr/x86_64-redhat-linux/lib64/libverticaodbc.so failed
attempt to open /usr/x86_64-redhat-linux/lib64/libverticaodbc.a failed
attempt to open /usr/local/lib64/libverticaodbc.so failed
attempt to open /usr/local/lib64/libverticaodbc.a failed
attempt to open /lib64/libverticaodbc.so failed
attempt to open /lib64/libverticaodbc.a failed
attempt to open /usr/lib64/libverticaodbc.so failed
attempt to open /usr/lib64/libverticaodbc.a failed
attempt to open /usr/x86_64-redhat-linux/lib/libverticaodbc.so failed
attempt to open /usr/x86_64-redhat-linux/lib/libverticaodbc.a failed
attempt to open /usr/lib64/libverticaodbc.so failed
attempt to open /usr/lib64/libverticaodbc.a failed
attempt to open /usr/local/lib/libverticaodbc.so failed
attempt to open /usr/local/lib/libverticaodbc.a failed
attempt to open /lib/libverticaodbc.so failed
attempt to open /lib/libverticaodbc.a failed
attempt to open /usr/lib/libverticaodbc.so failed
attempt to open /usr/lib/libverticaodbc.a failed
ld: cannot find -lverticaodbc

ld 没有从 /opt/vertica/lib64 中找到 verticaodbc。

谁能提供一些线索？非常感谢！

Answer 1

ld 是 静态 linker。 ld.so 是dynamic linker（而ldconfig & ldd 与动态链接器相关）。

您需要在链接时将-L/opt/vertica/lib64/ 添加到您的ld 参数中（并且您通常应该使用gcc 或g++ 链接）。实际上，这意味着编辑您的构建基础架构 - 例如你的Makefile - 添加几十个字符。

见ld.so(8)、ldd(1)、ld(1)、ldconfig(8)

另请阅读Drepper's paper: How To Write Shared Libraries、Program Library HowTo 和Levine's book: Linkers and Loaders