perl -i -ne 'print unless /\bsome string\b/' file
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broquaint

Hi. Thank for the quick response. I wanted to know if you can give me the code as a part of a script and not as a stand alone command Thanks Ahead

Assuming your file isn't too big (i.e will comfortably fit in memory)

open(my $fh, "<+", "your_file") or die("ack: $!");
my @data = <$fh>;
seek $fh, 0, 0;

my $newsize = 0;
for(@data) {
  next unless /\bsome string\b/;
  print $fh;
  $newsize += length;
}

truncate $fh, $newsize;
close $fh;
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Or if the file is too big to be read entirely into memory

open(my $read,  "<", "your_file") or die("ack: $!");
open(my $write, ">", "tmpfile$$") or die("ack: $!");

while(<$read>) {
  next unless /\b some string\b/;
  print $write;
}

close $read;
close $write;

rename $write, $read;
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See. perlopentut and perlfunc for more info.
HTH

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broquaint

while (my $line = readline STDIN) {
    # If the line matches the expression then skip the line.
    # Note the use of /x 
    if ( $line =~ /\b word \b/x ) {
        # Skip to the the next iteration
        next;
    }

    print $line;
}
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Save the code below to x.pl. Invoke with 'perl x.pl <filename>...'.

#!/usr/bin/perl -i -n
print unless /\bsome string\b/;
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90% of every Perl application is already written. ⇒

dragonchild

cat mydata | grep -v "my strange string" > my_new_data
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Yay, my first "Useless use of cat" award! This works just as well:

grep -v "my strange string" mydata > my_new_data

Pardon me for pointing out the useless use of cat.

SCNR

by this command I'm getting the exact opposit result from the one I wanted I'm getting a file that contains only the lines I wanted to delete. what good does that do?