How does passthrough printing work?
Passthrough printing allows a host computer to send a print job through the user's terminal (emulator) and out to an attached printer. It is sometimes called "local print", "attached print" or "slave print". This means the user must be logged in to the host. The host then sends a sequence of characters that causes the telnet or terminal emulation software to redirect its output to a local printer until a similar sequence is received to turn off the passthrough printing.