Hi singho,
There are several things wrong here.
1. According to your post title, do you what the 5th Element of the whole file, or each line in the file?
If your intention is the 5th Element of the whole file, then do this:
my @string;
open(SYSLOG, "/tmp/log100lines") or die "Can't open file: $!\n";
foreach my $line (<SYSLOG>) {
chomp $line;
push @string, $line
}
print $string[4],$/;
2. But it seem, to me you want the 5th element of each line, which in that case you need do this:
open(SYSLOG, "/tmp/log100lines") or die "Can't open file: $!\n";
foreach my $line (<SYSLOG>) {
chomp $line;
my @string = split(/ /, $line); ## remove the function join
print "$string[4]\n";
}
NOTE:
a.) The scope of the array variable "@string" in the both cases,
b.) In the second script, you don't need the function join, because it Joins the separate strings of LIST into a single string with fields separated by the value of EXPR which in your case is ',', so your 5th element of each line has an uninitialized value.
That been said, there are a number of things, I think one should take note:
- use these pragma: warnings and strict
- use lexically scoped file-handles and use 3 -argument open function like
open my $fh, '<', "file_to_open" or die "can't open file: $!";
- use a while loop, to walk through a file, step-wise like:
while(<$fh>){
...
}
- close all opened file handles
- Please, also check your shebang line
If you tell me, I'll forget.
If you show me, I'll remember.
if you involve me, I'll understand.
--- Author unknown to me
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Thanks a lot for your help a explantion, i ended up using join, since the above with just split failed eariler, may be i missed something before. I tried using the above code it worked neatly. Thanks a lot.
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After splitting your $line into pieces you are joining it back into one, so there is no 5th element (sad, Leeloo, isn't it?). If you remove the join bit, it should work assuming that your line has 5 elements...
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... what could be the issue here.
Allow Perl to suggest what the issue might be by using the warnings pragma, which would have warned you that $string[4] was undefined (and if you're a beginner, also diagnostics for more verbose suggestions). In addition, I would strongly suggest using the strict pragma to disallow certain practices that experience has shown to be problematic, e.g., use of variables that have not been pre-declared. So:
use strict;
use warnings;
use diagnostics; # when you are desperate
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