Question

I have a simple log file which is very messy and I need it to be neat. The file contains log headers, but they are all jumbled up together. Therefore I need to sort the log files according to the log headers. There are no static number of lines – that means that there is no fixed number of lines for the each header of the text file. And I am using perl grep to sort out the headers.

The Log files goes something like this:

Car LogFile Header
<text>
<text>
<text>
Car LogFile Header
<text>
Car LogFile Header
<and so forth>

I have done up/searched a simple algorithm but it does not seem to be working. Can someone please guide me? Thanks!

#!/usr/bin/perl

#use 5.010; # must be present to import the new 5.10 functions, notice 
#that it is 5.010 not 5.10


my $srce = "./root/Desktop/logs/Default.log";
my $string1 = "Car LogFile Header";
open(FH, $srce);
my @buf = <FH>;
close(FH);
my @lines = grep (/$string1/, @buffer);

After executing the code, there is no result shown at the terminal. Any ideas?

Answer 1

I think you want something like:

 my $srce = "./root/Desktop/logs/Default.log";
 my $string1 = "Car LogFile Header";

 open my $fh, '<',  $srce or die "Could not open $srce: $!";

 my @lines = sort grep /\Q$string1/, <$fh>;
 print @lines;

Make sure you have the right file path and that the file has lines that match your test pattern.

It seems like you are missing a lot of very basic concepts and maybe cutting and paste code you see elsewhere. If you’re just starting out, pick up a Perl tutorial such as Learning Perl. There are other books and references listed in perlfaq2.