Technical data

This was ﬁxed in DCPS V1.4 by enabling the KEEPALIVE option for such

TCP/IP connections. However, if your system is conﬁgured for unusually

long KEEPALIVE timeouts, you may continue to see this problem. If so,

you may recover by deleting the job (DELETE/ENTRY) or stoping the queue

(STOP/QUEUE/RESET).

13.2.8 Problems with VFC Files Containing Large Control Fields

If you printed a VFC-formatted ﬁle that utilized a ﬁxed-length control ﬁeld larger

than two (2) bytes, the DCPS symbiont could abort with an access violation

(ACCVIO) or other error.

13.2.9 ANSI Text Not Wrapped Properly When Using a Form

If you printed ANSI text with a form that speciﬁed the /WRAP qualiﬁer, the

input records were sometimes broken into output line segments that exceeded the

usable line width implied by the form.

13.3 DCPS Version 1.4 Changes

This section describes changes made in DCPS V1.4.

13.3.1 Support for Raw TCP/IP Connections

DCPS V1.4 adds the ability to communicate with printers via raw TCP/IP sockets.

Raw TCP is a network protocol that utilizes the TCP/IP protocol directly without

any additional interpretation of the TCP data stream. It is supported by many

printer Network Interface Cards (NICs), print servers, and terminal servers.

Table A–1 lists commonly-used raw TCP/IP port numbers.

There are other printer protocols that layer upon TCP/IP, including CPAP

(Common Printer Access Protocol), LPD, and Telnet. DCPS uses CPAP to

communicate with DIGITAL PrintServer printers. DCPS does not support LPD

or Telnet.

To communicate with your printer using raw TCP/IP, the NIC, print server or

terminal server that you use to connect your printer to the network must provide

a raw TCP/IP port. Further, this raw TCP/IP port must support bidirectional

communication between the printer and your OpenVMS system. DCPS does not

work with unidirectional ports, such as those found on the NICs for the DEClaser

3500 and 5100 printers, the RapidPrint 200 and 500, and HP JetDirect cards that

interface with the printer via its XIO (versus MIO) slot.

For more information about raw TCP/IP connections and creating queues that

utilize them, refer to the DECprint Supervisor for OpenVMS System Manager’s

Guide and comments in DCPS$STARTUP.COM.

13.3.2 ‘‘IP_CPAP’’ Replaces ‘‘TCPIP’’ Connection Type

In previous DCPS versions, a ‘‘tcpip/...’’ syntax was used in DCPS$STARTUP.COM

to specify communication with a DIGITAL PrintServer printer via TCP/IP.

In DCPS V1.4, a new ‘‘ip_cpap/...’’ syntax is introduced to replace the ‘‘tcpip/...’’

syntax. CPAP (Common Printer Access Protocol) is the network protocol

supported by DIGITAL PrintServer printers, and is just one of many TCP/IP

printer-related network protocols. The ‘‘tcpip/...’’ syntax is no longer recommended

because of its ambiguity, though DCPS continues to support it.

DCPS Version 1.4 Information 13–3