Well, here is an example I ran on the redhat boxes at work and my debian box at home, it shows bad data on both systems if run enough (usually 20 iterations will do it). I also added a check for syswrite... doesn't seem to be writing short data.
#!/usr/bin/perl
use Fcntl qw(:DEFAULT :flock);
use strict;
my $FH;
my $fn = 'flockdata';
my $test_data = (join('','a'..'z')."\n") x 10;
#print length($test_data),"\n";
sysopen($FH,$fn,O_WRONLY|O_CREAT);
for(1..10) {
last unless fork();
}
for(1..20) {
die "FLOCK ERROR\n" unless flock($FH,LOCK_EX);
die "SYSWRITE ERROR\n" unless syswrite($FH,$test_data,length($test_d
+ata)) == \
length($test_data);
flock($FH,LOCK_UN);
}
close $FH;
and to run it when named testflock.pl
perl -e 'system(q{perl testflock.pl ; ls -al flockdata; rm flockdata})
+ for 1..20'
- Ant
- Some of my
best work - (1 2 3)
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