8. incoming messages for users will now send a 'new message' message (instead

[spider.git] / perl / cluster.pl

diff --git a/perl/cluster.pl b/perl/cluster.pl
index 8502cbaba6b3d44bc4bd8935a566fd6c042d8ce4..5e4dd4d9efcc92880361e07a55bba4298c78a249 100755 (executable)
--- a/perl/cluster.pl
+++ b/perl/cluster.pl
@@ -20,6 +20,20 @@ BEGIN {
        
        unshift @INC, "$root/perl";     # this IS the right way round!
        unshift @INC, "$root/local";
+
+       # try to create and lock a lockfile (this isn't atomic but 
+       # should do for now
+       $lockfn = "$root/perl/cluster.lock";       # lock file name
+       if (-e $lockfn) {
+               open(CLLOCK, "$lockfn") or die "Can't open Lockfile ($lockfn) $!";
+               my $pid = <CLLOCK>;
+               chomp $pid;
+               die "Lockfile ($lockfn) and process $pid exist, another cluster running?" if kill 0, $pid;
+               close CLLOCK;
+       }
+       open(CLLOCK, ">$lockfn") or die "Can't open Lockfile ($lockfn) $!";
+       print CLLOCK "$$\n";
+       close CLLOCK;
 }
 
 use Msg;
@@ -42,6 +56,7 @@ use Bands;
 use Geomag;
 use CmdAlias;
 use Local;
+use Fcntl ':flock'; 
 
 use Carp;
 
@@ -51,7 +66,8 @@ package main;
 $systime = 0;                                  # the time now (in seconds)
 $version = "1.23";                             # the version no of the software
 $starttime = 0;                 # the starting time of the cluster   
- 
+$lockfn = "cluster.lock";       # lock file name
+      
 # handle disconnections
 sub disconnect
 {
@@ -150,6 +166,7 @@ sub cease
                disconnect($dxchan) unless $dxchan == $DXProt::me;
        }
        Log('cluster', "DXSpider V$version stopped");
+       unlink $lockfn;
        exit(0);
 }
 
@@ -281,8 +298,6 @@ eval {
 };
 dbg('local', "Local::init error $@") if $@;
 
-
-
 # print various flags
 #print "useful info - \$^D: $^D \$^W: $^W \$^S: $^S \$^P: $^P\n";