15、系统管理脚本实用指南

系统管理脚本实用指南

在Unix或Linux系统管理中，shell脚本是非常实用的工具。下面将详细介绍几个实用的系统管理脚本。

1. 环境验证脚本（validator）

环境验证脚本用于检查用户环境变量的有效性。以下是脚本代码：

if [ ! -d ${HOME:?"You need to have your HOME set to your home directory"} ]
then
  echo "** HOME set to $HOME, but it's not a directory."
  errors=$(( $errors + 1 ))
fi
# Our first interesting test: Are all the paths in PATH valid?
oldIFS=$IFS; IFS=":"     # IFS is the field separator. We'll change to ':'.
for directory in $PATH
do
  if [ ! -d $directory ] ; then
    echo "** PATH contains invalid directory $directory."
    errors=$(( $errors + 1 ))
  fi
done
IFS=$oldIFS             # Restore value for rest of script.
# The following variables should each be a fully qualified path,
#   but they may b