Incorporating Erik's IPC file locking in feCodeGen

src/epics/util/lib/IPCmonitor.pm

 package CDS::IPCmonitor;
 use Exporter;
+use Fcntl qw(:flock);
 use File::Path;
 @ISA = ('Exporter');
 
@@ -239,8 +240,11 @@ my @ipcxMaxNum = (-999,-999,-999,-999);
    	open(TOUCH, ">>$iFile");
    	close(TOUCH);
    }
+
    open(IPCIN, "<$iFile") || die "***ERROR: IPCx parameter file $iFile not found\n";
+   flock(IPCIN, LOCK_SH) || die "***ERROR: IPCx parameter file $iFile not locked: $!\n";
    chomp(@inData=<IPCIN>);
+   flock(IPCIN, LOCK_UN) || die "***ERROR: IPCx parameter file $iFile not unlocked: $!\n";
    close IPCIN;
 
    #

src/epics/util/lib/IPCx.pm

@@ -2,6 +2,7 @@ package CDS::IPCx;
 use File::Path qw( make_path );
 use Exporter;
 use File::Path;
+use Fcntl qw(:flock);
 @ISA = ('Exporter');
 
 #//	\page IPCx IPCx.pm
@@ -344,8 +345,11 @@ if ($::ipcxCnt > 0) {
      open(TOUCH, ">>$iFile");
      close(TOUCH);
    }
+
    open(IPCIN, "<$iFile") || die "***ERROR: IPCx parameter file $iFile not found\n";
+   flock(IPCIN, LOCK_SH) || die "***ERROR: Failed to lock file $iFIle: $!\n";
    chomp(@inData=<IPCIN>);
+   flock(IPCIN, LOCK_UN) || die "***ERROR: Failed to unlock file $iFIle: $!\n";
    close IPCIN;
 
    #
@@ -586,7 +590,9 @@ $ipcxRcvrCnt = 0;
    # Check if there are any IPCx modules to add to the IPCx parts matrix
    #
    if ($ipcxNotFound > 0) {
+
       open (IPCOUT, ">>$iFile") || die "***ERROR: Could not open IPCx parameter file $iFile for output\n";
+      flock (IPCOUT, LOCK_EX) || die "***ERROR: Failed to lock IPCx parameter file $iFile for output: $!\n";
 
       $ipcxRate = 983040/$::rate;
       $ipcxNew = 0;
@@ -664,6 +670,7 @@ $ipcxRcvrCnt = 0;
          }
       }
 
+      flock (IPCOUT, LOCK_UN) || die "***ERROR: Failed to unlock IPCx parameter file $iFile for output: $!\n";
       close IPCOUT;