Author: Stefan Seyfried <seife+obs@b1-systems.com>

Report an error if we cannot lock the serial port and hint on the
possible problem.
Be a bit paranoid about buffer overruns when reporting locking problems.

diff --git a/src/SerialImp.c b/src/SerialImp.c
index d20adcb..8ead1cd 100644
--- a/src/SerialImp.c
+++ b/src/SerialImp.c
@@ -5296,12 +5296,12 @@ int lib_lock_dev_lock( const char *filename, int pid )
 	printf("LOCKING %s\n", filename);
 	if ( dev_testlock( filename ) )
 	{
-		report( "fhs_lock() lockstatus fail\n" );
+		report_error( "lib_lock_dev_lock() lockstatus fail, are you in group 'lock'?\n" );
 		return 1;
 	}
 	if ( dev_lock( filename ) )
 	{
-		sprintf( message,
+		snprintf( message, 80,
 			"RXTX fhs_lock() Error: creating lock file for: %s: %s\n",
 			filename, strerror(errno) );
 		report_error( message );