Hi monks,

I'd like to split a file to three parts and search different strings.As GrandFather's reply and Super Search,Tie::File seems the best way.Below is my code: 
use strict;
use warnings;
use Tie::File;


my $file_name = 'test.txt';
my @name;
tie @name, 'Tie::File' ,$file_name;
die "error!!!" unless defined (my $pid_1 = fork());
 exit search_string(0,9999,"8888") unless ($pid_1);
die "error!!!" unless defined (my $pid_2 = fork());
exit search_string(10000,19999,"18888") unless ($pid_2);
die "error!!!" unless defined (my $pid_3 = fork());
exit search_string(20000,29999,"28888") unless ($pid_3);
wait;
wait;
wait;
untie @name;
sub search_string {
    my ($from,$to,$string) = @_;
    for ($from .. $to) {
        print "the $_ th line of test.txt is $string\n" if $name[$_] =
+~ /^$string$/x;
    }
}

__test.txt__
1
2
3
...
29998
29999
30000

[download]
It works quite well for the FIRST time,but....Look: 
# first time
the 8887 th line of test.txt is 8888
the 18887 th line of test.txt is 18888
the 28888 th line of test.txt is 28888

#second time
the 8888 th line of test.txt is 8888
the 18888 th line of test.txt is 18888
the 28889 th line of test.txt is 28888

#third time
the 8887 th line of test.txt is 8888
the 28887 th line of test.txt is 28888
Use of uninitialized value in pattern match (m//) at serarch_file.pl l
+ine 42, <$
fh> line 29884.
Use of uninitialized value in pattern match (m//) at serarch_file.pl l
+ine 42, <$
fh> line 29884.
Use of uninitialized value in pattern match (m//) at serarch_file.pl l
+ine 42, <$
fh> line 29884.
Use of uninitialized value in pattern match (m//) at serarch_file.pl l
+ine 42, <$
fh> line 29884.
Use of uninitialized value in pattern match (m//) at serarch_file.pl l
+ine 42, <$
fh> line 29884.

[download]
Please advice!

I am trying to improve my English skills, if you see a mistake please feel free to reply or /msg me a correction

In reply to regarding Tie::File by xiaoyafeng

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