PMDF System Manager's Guide
PMDF-REF-6.0

Printer channels may be used to route e-mail to a spooled printer queue. While the current implementation of the printer channel is designed for use with "dumb" printers, it is flexible enough to do sophisticated printing on "intelligent" printers such as PostScript printers as described in e.g., Section 27.6.4 .

The addressing format required to direct e-mail to a printer channel is presented in Section 27.6.2 .

On OpenVMS systems, the printer channel interfaces to printer queues via the $SNDJBC system service. On UNIX systems, the channel forks a child to print each message file. The command used to issue the print request may be controlled with the PRINT_COMMAND option described in Section 27.6.1.2 . By default, an lpr command is used.
On OpenVMS, do not ever specify an execution queue for a printer channel queue; (i.e., make sure that the printer channel queue is an output queue). Picture the following scenario: a printer channel is marked headeromit (or headerbottom) and a message containing only a command procedure is sent to the printer channel for "printing". This message --- a command procedure --- will then be submitted to the execution queue under the guise of the user running the printer channel, who is typically a privileged user.