最近Webmin相关功能需要Authen::Libwrap，安装时遇到问题，输出日志如下：
cpanm (App::cpanminus) 1.7040 on perl 5.022001 built for x86_64-linux-gnu-thread-multi Work directory is /root/.cpanm/work/1525944650.23506 You have make /usr/bin/make You have LWP 6.15 You have /bin/tar: tar (GNU tar) 1.28 Copyright (C) 2014 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Written by John Gilmore and Jay Fenlason. You have /usr/bin/unzip Searching Authen::Libwrap () on cpanmetadb ... --> Working on Authen::Libwrap Fetching http://www.cpan.org/authors/id/D/DM/DMUEY/Authen-Libwrap-0.23.tar.gz -> OK Unpacking Authen-Libwrap-0.23.tar.gz Entering Authen-Libwrap-0.23 Checking configure dependencies from META.json Checking if you have ExtUtils::Install 1.46 ... Yes (2.04) Checking if you have Module::Build 0.42 ... Yes (0.4216) Configuring Authen-Libwrap-0.23 Running Build.PL enter include directory to use: [/usr/include ]/usr/include enter library directory to use: [/usr/lib ]/usr/lib Created MYMETA.yml and MYMETA.json Creating new 'Build' script for 'Authen-Libwrap' version '0.23' -> OK Checking dependencies from MYMETA.json ... Checking if you have ExtUtils::CBuilder 0 ... Yes (0.280221) Checking if you have Test::More 0 ... Yes (1.001014) Checking if you have Scalar::Util 0 ... Yes (1.41) Checking if you have Test::Exception 0 ... Yes (0.43) Building and testing Authen-Libwrap-0.23 Building Authen-Libwrap Error: Function definition too short '/ * EOF * /' in Libwrap.xs, line 32 x86_64-linux-gnu-gcc -I/usr/lib/x86_64-linux-gnu/perl/5.22/CORE -DXS_VERSION="0.23" -DVERSION="0.23" -fPIC -I/usr/include -c -D_REENTRANT -D_GNU_SOURCE -DDEBIAN -fwrapv -fno-strict-aliasing -pipe -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -O2 -g -o lib/Authen/Libwrap.o lib/Authen/Libwrap.c lib/Authen/Libwrap.xs:9:18: fatal error: tcpd.h: No such file or directory compilation terminated. error building lib/Authen/Libwrap.o from 'lib/Authen/Libwrap.c' at /usr/share/perl/5.22/ExtUtils/CBuilder/Base.pm line 173. -> FAIL Installing Authen::Libwrap failed. See /root/.cpanm/work/1525944650.23506/build.log for details. Retry with --force to force install it.
解决方法很简单：
sudo apt-get install libwrap0 libwrap0-dev
然后重新尝试即可。