Quote:

Originally Posted by user_prady I tried almost all way using next , redo and last command in perl , But I can't get these syntax correctly in perl. I know its easy ,but still I cant find the efficient way using while and next statement in perl. I am trying to do the follwoing in perl Code: nawk ' { if($0 ~ /^\*Main Start/){ while( $0 !~ /^\*Main End/){ print $0; getline; } } } ' my.txt One more code I want to do it in perl pls give me some basic idea how to do it without creating any temporary files .. Code: TMP=/tmp/my_tmp$$ nawk ' /\*Main End/{ split(x,arr,",") print "Loop " arr[1] }; {x=$0 } ' my.txt > $TMP nawk '{ if($0 ~ /^Loop/){ loop = $2 next; } if($0 ~ /^\*Main Start/){ printf "\nrepeat (" print loop } ' $TMP $my.txt Thanks & Regards, user_prady

my @buffer;
$#buffer = 1;
open(IN, $file)|| die("Could not open file");
 
while(<IN>){
        push@buffer => $_;
        shift@buffer;
}
close(IN);
open(IN, $file)|| die("Could not open file");
while(<IN>){ 
       print $buffer[0] if/^\*Main Start/ ;
}
close(IN);

Quote:

Originally Posted by KevinADC You could use the Tie::File module for this which avoids the brute approach "era" mentioned. With Tie::File you treat a file like a perl array, so if you find a pattern in a certain line you just use simple array indexing to go back one line in the file. See the Tie::File (a perl core module) documentation for usage details.

Can't locate Tie/File.pm in @INC (@INC contains: /usr/perl5/5.00503/sun4-solaris /usr/perl5/5.00503 /usr/perl5/site_perl/5.005/sun4-solaris /usr/perl5/site_perl/5.005 .) at ./mdl.pl line 5.
BEGIN failed--compilation aborted at ./mdl.pl line 5.

use strict;
use warnings;
my $flag = 0;
my $last_line;
while(<DATA>){
   if(/^\*Main Start/){
      $flag = 1;
   }
   elsif($flag && /^\*Main End/) {
         $numbers = (split(',',$last_line))[0];
         $last_line = '';
         $flag = 0; 
         print $numbers,"\n";
   }
   else {
      $last_line = $_;
      next;
   }
}	
__DATA__
*Init End
*Main Start
*Comment Reset Timers
000000,0000,0,0,0,0,0,1,0
000000,0000,0,0,0,0,1,1,0 
*Comment Control Frame at 1.04596 ms
000000,0400,0,0,0,0,1,0,1
2418A4,0000,0,1,3,0,0,0,0 
049C00,0000,0,0,2,0,0,0,0
*Comment Control Frame at 1.04673 ms
*Comment Control Frame at
000002,0000,0,0,0,0,1,0,1
241002,0000,0,1,3,0,0,0,0
000100,0000,0,0,2,0,0,0,0
*Comment Control Frame at
000004,0000,0,0,0,0,1,0,1
241002,0000,0,1,3,0,0,0,0
000000,0000,0,0,2,0,0,0,0
*Comment Frame 13 at ** us,,,,,,,,
000005,7E3D,0,0,0,0,1,0,1
*Main End,,,,,,,,