无限期的循环？如果联机或脱机，请检查两台打印机-如果关闭，请发送电子邮件

Question

我有一个正在无限期循环的脚本--有两台打印机要检查一次-- printer01和printer02。如果他们被关闭或关闭，然后发送电子邮件。为什么它在第一个printer01上无限期地循环？

#!/bin/ksh
c=1
while [[ $c -le 3 ]]; do
STATUS=$(lpstat -printer0$c| grep 'READY' | awk '{print $3}')

if [[  ! $STATUS == "DOWN" ||! $STATUS == "OFF" ]] ; then

        #create email summary and send

        today=`date +%m%d%Y`

        echo "*** START EMAIL SUMMARY ***                                    " > /lsf10/monitors/lpstat_email_$today.txt
        echo "*                                                              " >> /lsf10/monitors/lpstat_email_$today.txt
        echo "* Date - `date`                                                " >> /lsf10/monitors/lpstat_email_$today.txt
        echo "*                                                              " >> /lsf10/monitors/lpstat_email_$today.txt
        echo "* Start time   => $s_time                                      " >> /lsf10/monitors/lpstat_email_$today.txt
        echo "* Current time => `date +%H:%M:%S`                             " >> /lsf10/monitors/lpstat_email_$today.txt
        echo "*                                                              " >> /lsf10/monitors/lpstat_email_$today.txt
        echo "* Printer email message will be here for you to modify         " >> /lsf10/monitors/lpstat_email_$today.txt
        echo "* Please investigate.                                          " >> /lsf10/monitors/lpstat_email_$today.txt
        echo "*                                                              " >> /lsf10/monitors/lpstat_email_$today.txt
        echo "*** END EMAIL SUMMARY ***                                      " >> /lsf10/monitors/lpstat_email_$today.txt

        `mail -s "Mobius Printer Down Alert!" "email1,email2" < /lsf10/monitors/lpstat_email_$today.txt`
fi
c = $c + 1
done
exit

Answer 1

考虑在每个外部命令之后添加错误检查。

您可以使用ksh -x来运行您的脚本来查看您的错误，这会打开调试模式。还可以通过在脚本中添加set -x来做到这一点。

您的脚本正在循环，因为变量$c没有按照您的想法设置。

您可能需要检查退出代码($?)从每个外部命令中，还检查lpstat返回的stdout是否为空或任何错误，并验证邮件程序是否在路径和可执行文件等上。

尝试另一种方法，如下所示：

#!/bin/ksh
typeset +i c=1 
while (( c <= 2 )); do
    STATUS=$(lpstat -printer0$c| grep 'READY' | awk '{print $3}')
    if [[  ! $STATUS == "DOWN" ||! $STATUS == "OFF" ]] ; then
        #create email summary and send

        today=`date +%m%d%Y`
        outfile=/tmp/lpstat_email_$today.txt  # use your own path

        echo "*** START EMAIL SUMMARY ***                                    " > ${outfile}
        echo "*                                                              " >> ${outfile}
        echo "* Date - `date`                                                " >> ${outfile}
        echo "*                                                              " >> ${outfile}
        echo "* Start time   => $s_time                                      " >> ${outfile}
        echo "* Current time => `date +%H:%M:%S`                             " >> ${outfile}
        echo "*                                                              " >> ${outfile}
        echo "* Printer email message will be here for you to modify         " >> ${outfile}
        echo "* Please investigate.                                          " >> ${outfile}
        echo "*                                                              " >> ${outfile}
        echo "*** END EMAIL SUMMARY ***                                      " >> ${outfile}

        `mail -s "Mobius Printer Down Alert!" "email1,email2" < ${outfile}`
    fi  
    let c=$(( c + 1 ))
done
exit