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http://dgd2010.blog.51cto.com/1539422/1661362
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欢迎信息，一般包括Linux发行版本名称，内核版本、操作系统位数
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操作系统当前信息，如操作系统负载，进程数量，文件系统使用情况，当前用户登录数，内存（含swap）使用情况，IP地址
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文档和帮助信息
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可更新的软件包和可升级的安全补丁
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#Long running operations (such as network calls) or resource intensive scripts should cache output, and only update that output if it is deemed expired. For instance:
#/etc/update-motd.d/50-news
#!/bin/sh
out=
/var/run/foo
script=
"w3m -dump http://news.google.com/"
if
[ -f
"$out"
];
then
# Output exists, print it
echo
cat
"$out"
# See if it's expired, and background update
lastrun=$(stat -c %Y
"$out"
) || lastrun=0
expiration=$(
expr
$lastrun + 86400)
if
[ $(
date
+%s) -
ge
$expiration ];
then
$script >
"$out"
&
fi
else
# No cache at all, so update in the background
$script >
"$out"
&
fi
#Scripts should emit a blank line before output, and end with a newline character. For instance:
#/etc/update-motd/05-lsb-release
#!/bin/sh
echo
lsb-release -a
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