Hello. I have a DBM file which contains all the members online. 
use fcntl qw(:DEFAULT :flock);
use DB_File; 

$lck = $path/whosonline . ".lockfile";
sysopen(DBLOCK, $LCK, O_RDONLY | O_CREAT) or die "can't open $lck: $!"
+;

flock(DBLOCK, LOCK_SH) or die "cant lock_sh $lck: $1";

dbmopen %who, "$path/whosonline", 0666  or die "Can't open FILENAME: $
+!\n";# open database, accessed through %mname

tie %who, "DB_File", "$path/whosonline" or die "Can't open FILENAME: $
+!\n";        # open database  tie hash to db

$V = $who{$points};                # retrieve from database this is th
+e key
$who{$Account::cata_acc} = "$time";                # put value into da
+tabase      this is the value
if (exists $who{"$Account::cata_acc"}) {       # check whether in data
+base
}
untie %who ;
dbmclose %who;                # close the database
close DBLOCK;
#done checking whosonline

[download]
Should I lock the file like this? and is it the right way?

Edit: 2001-03-03 by neshura

In reply to Should I lock this DBM File? by tanger

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