in reply to delete a line by a string

A simple one-liner coming up 
perl -i -ne 'print unless /\bsome string\b/' file

[download]
See. perlrun for more info on perl's commandline arguments.
HTH

_________
broquaint

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Re: Re: delete a line by a string
by moked (Beadle) on Apr 02, 2003 at 14:38 UTC
    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
[reply]
      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;

      [download]
      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;

      [download]
      See. perlopentut and perlfunc for more info.
      HTH

      _________
      broquaint

[reply]
[d/l]
[select]
      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;
}

      [download]
[reply]
[d/l]

      Save the code below to x.pl. Invoke with 'perl x.pl <filename>...'. 

      #!/usr/bin/perl -i -n
print unless /\bsome string\b/;

      [download]
      90% of every Perl application is already written. ⇒
      dragonchild
[reply]
[d/l]

In Section Seekers of Perl Wisdom