CODEWITHSUNDEEP
bashperlshell
biren.K
biren.K

Reputation: 247

delete lines between two patterns without deleting the pattern

i have a file like below 

[NAMES]
biren
bikash
dibya

[MAIL]
biren_k
bikash123
dibya008

my output should be like below

[NAMES]

[MAIL]

i tried the below code just to remove the lines between NAMES and MAIL, but it did not work.

sed -n '/NAMES/{p; :a; N; /MAIL/ba; s/.*\n//}; p' input.txt

Can anyone help please... i would prefer perl code if any...

NOTE: like [NAMES] and [MAIL] , i have a lot of headers in my actual file. here i have just shown two headers. I have to replace the contents below the headers(not all, only selected headers which are at random line numbers) with new contents. but first i nedd to delete the contents below them. Thats why i need my output like this. Any suggestions please...

Upvotes: 0

Views: 182

Answers (4)

biren.K
biren.K

Reputation: 247

I found solution to my problem here:

my @name_var = ();
while (<STDIN>)
{
  last if ($_ =~ /^\n/ );
  push(@name_var, $_);
}

my @mail_add = ();
while (<STDIN>)
{
  last if ($_ =~ /^\n/ );
  push(@mail_add, $_);
}

open(my $var, "input.txt") || die("Input File not found");
open(my $out, ">temp.txt") || die("Temp File not created");
while($line = <$var>)
{
   # print $line;
    if( $line =~ /\[NAMES\]/)
    {
      print $out $line;
      print $out $name_var;

     while(($line = <$var>) && ($line !~ /^\n/))
      {
      }
    }

    if( $line =~ /\[MAIL\]/)
    {
      print $out $line;
      print $out $mail_add;

     while(($line = <$var>) && ($line !~ /^\n/))
      {
      }
    }       
    print $tcf_out $line;
}

close($var);
close($out);
open($var1,">input.txt") || die("failed to open\n");
open($out1,"<temp.txt") || die("failed to open\n");
while($fl = <$out1>)
{ 
  print $var1 $fl;
}
close($var1);
close($out1);

Thank you all. I got the solution from stack overflow, perlmonk and few more sites related to perl.

Upvotes: 0

Pavel
Pavel

Reputation: 91

Just replace the lines between my @erase = qw[ and ]; with HEADERS you meant to empty out.

#!/usr/bin/env perl
use strict;
use warnings;

push @ARGV, 'file.txt';
# here list out the HEADERS
# which content you wanna erase
my @erase = qw[
    NAMES
    MAIL
];

my %dump;
my $header;
# build a hash from your file
while (<>) {
  if (/^\[([^\]]+)\]$/) {
    $header = $1;
    $dump{$header} = "";
    next;
  }
  $dump{$header} .= $_ if $header;
}

# replace the content
# with empty string
foreach (@erase) {
  $dump{$_} = "";
}

# now print it back to <STDOUT>
foreach (sort keys %dump) {
  print "[$_]\n$dump{$_}\n";
}

Upvotes: 0

ssr1012
ssr1012

Reputation: 2589

Please try this may be helpful on your question:

%hashes = (
"[NAMES]" => "<br/>kumar<br/>avi<br/><br/>\n",
"[MAIL]" => "<br/>biren_k<br/>bikash123<br/>dibya008<br/>\n"
);

my @arr = <DATA>;
foreach my $snarr(@arr)
{
    chomp($snarr);
    push(@newarr, "$snarr\n$hashes{$snarr}"), if( $hashes{$snarr} );
}

print @newarr;


__DATA__
[NAMES]
biren
bikash
dibya

[MAIL]
biren_k
bikash123
dibya008

Upvotes: 0

nu11p01n73R
nu11p01n73R

Reputation: 26667

You can modify sed as

$ sed '/\[NAMES\]/, /\[MAIL\]/ {/^\[/p; d}' input
[NAMES]
[MAIL]
biren_k
bikash123
dibya008

Upvotes: 1

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