perl文件锁

#cat config

10

 

 

#cat test_lock.pl

 

#!/bin/env perl
use strict;
use warnings;
print "Content-type: text/html\n\n";
use Fcntl qw(:flock SEEK_END);

my $conf = "config";
open(my $fp,"+<",$conf) or die $!;
my_lock($fp);
my @lines = <$fp>;
foreach $_ (@lines)
{
        chomp;
        print "$_\n";
        $_--;
}

truncate($fp, 0);
seek($fp, 0, 0);
print $fp join($/, @lines), $/;
my_unlock($fp);
close $fp;

################################################

sub my_lock
{
        my ($fh) = @_;
        flock($fh, LOCK_EX) or die $!;
}

sub my_unlock
{
        my ($fh) = @_;
        flock($fh, LOCK_UN) or die $!;
}