# reading open NEWSRC, "< $newsgroup_file" or die "Could not open newsgroup file $newsgroup_file\n"; unless (flock NEWSRC, LOCK_SH | LOCK_NB) { print "Contention: cannot get a shared lock the file, blocking ($!)...\n"; unless (flock NEWSRC, LOCK_SH) { die "ERROR: cannot get a shared file lock on $newsgroup_file: $!\n"; } } print "Initial newsrc read lock granted\n"; my @news_lines = ; close NEWSRC; # writing open NEWSRC, "+< $newsgroup_file" or die "Could not open newsgroup file $newsgroup_file\n"; unless (flock NEWSRC, LOCK_EX | LOCK_NB) { print "$group ($$): Contention: cannot get an exclusive lock the file,\n blocking ($!) ...\n"; unless (flock NEWSRC, LOCK_EX) { die "$group ($$): ERROR: cannot get an exclusive file lock on $newsgroup_file: ($!)\n"; } } print "$group ($$): Write lock granted\n"; print NEWSRC @news_lines or die "Disk full\n"; close NEWSRC;