Try  system('C:/BatchTest/test.bat') == 0 or print "error: $!\n";

(Update: maybe I should add that if system() fails to execute the command, it returns -1, and only then $! is guaranteed to hold a meaningful value... (so testing ... == -1 and print $! would be the proper way).  I suggested to check for a system() return value of zero, as then it would still print "error:" even in the rare case that the batch command should execute but not exit with zero (which typically means an error occurred on the command's side...) )