Specifying the Pathname
Each output-file option accepts a pathname argument that can specify a location and a name for the output file. The argument can include a drive name, directory, and file name. No space is allowed between the option and the argument.
If pathname includes a file name without an extension, the compiler gives the output a default extension. If pathname includes a directory but no file name, the compiler creates a file with a default name in the specified directory. The default name is based on the base name of the source file and a default extension based on the type of the output file. If you leave off pathname entirely, the compiler creates a file with a default name in a default directory.
Alternatively, the pathname argument can be a device name (AUX, CON, PRN, or NUL) rather than a file name. Do not use a space between the option and the device name or a colon as part of the device name.
Null device (no file created)
The following command line sends a mapfile to the printer:
CL /FmPRN HELLO.CPP