demo_name will be placed in the client_demos folder in the directory in which you have the City of Heroes game client installed. ".cohdemo" (without the quotation marks) will automatically be appended to the filename you give. The demo will continue recording until /demostop is used or you zone (exit mission, use train, etc). The .cohdemo file is a flat text file that describes what is happening in game. This text file can then be played back using the -demoplay command line switch. See Demo Recording for more information.