在安装mahimahi过程中，遇到了一些环境变量配置问题，特此记录和分享。

XCB

configure: error: Package requirements (xcb) were not met:No package 'xcb' foundConsider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.Alternatively, you may set the environment variables XCB_CFLAGS
and XCB_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.

解决方法：

sudo apt install xcb
sudo apt install libxcb*

pangocairo

configure: error: Package requirements (pangocairo) were not met:No package 'pangocairo' foundConsider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.Alternatively, you may set the environment variables PANGOCAIRO_CFLAGS
and PANGOCAIRO_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.

sudo apt-get install libpango1.0-dev

protobuf

configure: error: Package requirements (protobuf) were not met:No package 'protobuf' foundConsider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.Alternatively, you may set the environment variables protobuf_CFLAGS
and protobuf_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.

在网上查询了方法，输入

export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig

然后

./configure --prefix=/usr/local

仍然报错。
后来在这篇博客中找到了原因和方法，原因是缺少libprotobuf-dev库或库版本过低，执行

apt-get install libprotobuf-dev

后问题解决。