編譯ZeroMQ以支持Libsodium出現的“ No package 'libsodium' found”問題

在編譯zeromq以支持libsodium時出現找不到libsodium包問題：checking for sodium... no執行"./configure --prefix=/usr --with-libsodium"出現：

[root@localhost zeromq-4.1.2]#./configure --prefix=/usr --with-libsodium

checking for sodium... no
configure: error: Package requirements (libsodium) were not met:

No package 'libsodium' found

Consider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.

Alternatively, you may set the environment variables sodium_CFLAGS
and sodium_LIBS to avoid the need to call pkg-config.

根據提示：查看PKG_CONFIG_PATH環境變量，

echo $PKG_CONFIG_PATH

此時問空，原來如此。

加上pkg-config路徑即可

export PKG_CONFIG_PATH=/usr/lib/pkgconfig

此時再次./configure就通過。