c - 为什么 ld 无法从/etc/ld.so.conf 中的路径找到库？

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加入/etc/ld.so.conf，运行ldconfig，
(2) 检查一下:

 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 static linker . ld.so 是 dynamic linker (ldconfig & ldd 与动态链接器有关)。

您需要在 link 时将 -L/opt/vertica/lib64/ 添加到您的 ld 参数(并且您通常应该链接使用 gcc 或 g++)。实际上，这意味着编辑您的构建基础设施 - 例如您的 Makefile - 添加几十个字符。

参见 ld.so(8) , ldd(1) , ld(1) , ldconfig(8)

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