Hi Experts, I need a way to clear out the contents of a text file(or input file) after i am done using that text file. I am not looking to delete the file. Just clearing the contents of the file is enough. The reason is that , we are using an input file(txt file) to do some actions on some set of servers. Once those actions are completed i need to clear out the contents of the files so that nobody resuses those same contents when the action is taken on new set of servers. Below is my code. Just need to include the clear part, but not sure how? 
#!C:\Perl\bin\perl.exe
use Win32;
use IO::Handle;
use File::Find;
use strict;
use warnings;
use File::Copy qw(copy);

######################################################################
+##############
#This script is created to put the servers in unplanned outage as part
+ of the tasks#
#that are received to stop the monitoring on the servers
#due to some maintenance activity on the servers.
#
#
#

require "E:/Temp/inyrohs/omwNodeDetails.pm";


#expect values 'on|off'

my ($SEC,$MIN,$HOUR, $DAY, $MON, $YEAR)= (localtime) [0..6];

my $year=$YEAR+1900;
my $month=$MON+1;
my $day=$DAY;
my $date="$year\_$month\_$day";

my $LOG="E:/Temp/inyrohs/maintenanceMode_$date.log";

my $serverlist="E:/Temp/INYROHS/serverlist.txt";

 

 open( MYFILE, "E:/Temp/INYROHS/serverlist.txt") or die "Can't open '$
+serverlist': $!";

my @outagenodes=<MYFILE>;


#print "@outagenodes\n";

my $maintMode=$ARGV[0]; 

chomp($maintMode);

open (LOG,">> $LOG") or die "Can't open $LOG file: $!\n";

printf LOG ("\nTime is %02d:%02d:%02d.\nStarting the maintenance mode 
+process to turn $maintMode outages.\n\n", $HOUR, $MIN, $SEC);

#print "$date \n";

#print "starting the process \n";



#print "maintMode: $maintMode:\n";






if($maintMode =~ m/on/)

   {        


foreach my $NODES (@outagenodes)

       {
            

           my @parts=split /\./, $NODES;

           my $hostname=$parts[0];

           chomp($hostname);

           my $fqdn = getNodeAttributes($hostname,"PrimaryNodeName");

           print "$hostname\n";
            
            #printLog("Node: $NODES, processing...\n");

            #print "entered loop \n";

    

           my $cmd="ovownodeutil.cmd -outage_node -unplanned -disable_
+heartbeat -delete_msgs -node_name $fqdn -$maintMode ";

            print "$cmd\n";

            `$cmd`;

            print "done with command\n";
 
        }

   }

         elsif($maintMode=~ m/off/)

        
   {


foreach my $NODES (@outagenodes)

       {


           my @parts=split /\./, $NODES;

           my $hostname=$parts[0];

           chomp($hostname);

         my  $fqdn = getNodeAttributes($hostname,"PrimaryNodeName");

           print "$hostname\n";


           printLog("Node: $NODES, processing...\n");

           printLog("Bringing the server $NODES out of outage.\n");

           my $cmd="ovownodeutil.cmd -outage_node -unplanned -disable_
+heartbeat -delete_msgs -node_name $NODES -$maintMode";

           my $cmdresopcmona="ovdeploy -cmd \"ovc -restart opcmona\" -
+host $NODES";

           my $cmdresopcle="ovdeploy -cmd \"ovc -restart ocpmona\" -ho
+st $NODES"; 
      
           print "$cmd\n";

           `$cmd`; 

           print "$cmdresopcmona\n";
 
           `$cmdresopcmona`; 
            

           print "$cmdresopcle\n";

           `$cmdresopcle`;                        
             
       }                      
            
           

  } 






sub printLog
{
    my ($logLine) = @_;
    chomp($logLine);
    $logLine=$logLine . "\n";
    print "$logLine"; print LOG "$logLine";
}

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In reply to Clear the contents of the text file by shroh

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