Going to a specific line in a file.

Jayesh Nair has asked for the wisdom of the Perl Monks concerning the following question:

Replies are listed 'Best First'.
Re: Going to a specific line in a file. by ikegami (Patriarch) on Jun 13, 2007 at 14:13 UTC
Tie::File still reads line by line, and has a lot of overhead. Alternative: `do { die("Premature EOF") if not defined <FILE>; } while $. < 14; my $line15 = <FILE>;` [download]	[reply] [d/l]
Re: Going to a specific line in a file. by marto (Cardinal) on Jun 13, 2007 at 14:04 UTC
Jayesh Nair, You may find the module Tie::File helpful. You should read the PerlMonks FAQ and How do I post a question effectively? since you posted this question in the wrong section of the forum. Hope this helps Martin	[reply]
Re: Going to a specific line in a file. by citromatik (Curate) on Jun 13, 2007 at 14:05 UTC
You can use the Tie::File module `use strict; use warnings; use Tie::File; my $file = shift @ARGV; tie my @arr, 'Tie::File', $file; #Update: (thanks Corion and JohnGG) #print $arr[15]."\n"; print $arr[14]."\n";` [download] citromatik	[reply] [d/l]
Re^2: Going to a specific line in a file. by johngg (Canon) on Jun 13, 2007 at 14:17 UTC
`print $arr[15]."\n";` <nit>That is the 16th line.</nit> Also, why not just interpolate into the string rather than using concatenation? `print qq{$arr[14]\n};` [download] Cheers, JohnGG	[reply] [d/l] [select]
Re: Going to a specific line in a file. by fenLisesi (Priest) on Jun 13, 2007 at 14:01 UTC
Unless your lines are of constant length, you have to go line by line. Cheers.	[reply]
Re: Going to a specific line in a file. by Anonymous Monk on Jun 13, 2007 at 19:38 UTC
#!/usr/bin/perl open file,"./testFile.txt" or die; while (<file>) { next if (1..6); --> this skips the first 6 lines. print "$_\n"; }	[reply]
Re: Going to a specific line in a file. by ctilmes (Vicar) on Jun 14, 2007 at 11:28 UTC
Displaying/buffering huge text files describes some methods for indexing text files for more fast/efficient jumping to a specific line.	[reply]
Re: Going to a specific line in a file. by Asmo (Monk) on Jun 14, 2007 at 20:56 UTC
Simplest method : `open (DATAFILE, $filename); @lines = <DATAFILE>; close(DATAFILE); print $lines[14];` [download]	[reply] [d/l]
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