demo.rsc

/system script
add name=test owner=mmv policy=\
    ftp,reboot,read,write,policy,test,password,sniff,sensitive,romon source={
:local content [/file get [/file find name=ip.txt] contents] ;
:local contentLen [:len $content];

:local lineEnd 0;
:local line "";
:local lastEnd 0;
:local domail false

:while ($lineEnd < $contentLen) do={
  :set lineEnd [:find $content "\n" $lastEnd];
  :if ([:len $lineEnd] = 0) do={
    :set lineEnd $contentLen;
  }
  :set line [:pick $content $lastEnd $lineEnd];
  :set lastEnd ($lineEnd + 1);
  :if ([:find "error" $line != "\n") do={
    :if ([/ping $line count=5] = 5) do={
       :put "$line" 
       :set domail true
#      /tool e-mail send to=test1@gmail.com subject="Can't ping $line"
#      /tool e-mail send to=test2@gmail.com subject="Can't ping $line"
    }
  }
}

:if $domail do={
       :put "Lets send mail!" 
#      /tool e-mail send to=test1@gmail.com subject="File ip.txt error" body=$content
#      /tool e-mail send to=test1@gmail.com subject="File ip.txt error" file=ip.txt
}

}