I have script like this:

open(INFILE,"<","words.txt")

my @X;
while(<INFILE>){
   push @X,(split(/\s+/,$_))[0]; ### choosing particluar column and pu
+shing all its values in single array
  }

$a = 0;
$main = 'temp.txt'; 
$mod = 'temp_mod.txt';
for (0..$#X)

{

$b = $main;
open b ;
open NEWFILE1, ">$mod" ;
while (<b>) { / $X[$a]   / or print NEWFILE1 }
close NEWFILE1;
$main = $mod;
$mod = $b;
$a++;
}

[download]

What it is doing: it is removing lines having "words" in single column in words.txt file. Which are stored in array @X. It opens file temp.txt, removes first word and save it in file temp_mod.txt. this later file is used again to remove second word from @X array and this loop runs by opening and closing temp.txt and temp_mod.txt

I have lot many words and many lines in file (60mb). So opening, removing line, closing, opening cycle consumes lot of time. Can I just open once a file and remove all lines together having words stored in words.txt

In reply to how to avoid opening and closing files by sagar_qwerty

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