RFC 448 (rfc448) - Page 1 of 3
Print files in FTP
Alternative Format: Original Text Document
NETWORK WORKING GROUP R.T. Braden REQUEST FOR COMMENT NO. 448 UCLA/CCN NIC #13299 February 27, 1973 UPDATES: RFC 354, 385, 454 PRINT FILES IN FTP INTRODUCTION ------------ Many of those who contributed to the definition of the FTP and RJE protocols have expressed varying degrees of uncertainty or unhappiness with the "print file" type in FTP. This RFC is intended to review the problem of print files in preparation for the forthcoming FTP meeting. Originally drafted on the basis of RFC 385, this RFC has been updated to reflect the terminology of the latest FTP document 454. (Changing the terminology doesn't solve the problem!) It turns out that the Network RJE protocol as presently defined (see NIC 12112) seems to force a particular interpretation of print files in FTP and in fact, this interpretation is probably different from the one assumed by most FTP implementors. VERTICAL FORMAT CONTROL ----------------------- What is a print file? Presumably it is a file which is intended to be sent (eventually) to a printer process to create a hard copy. Many operating systems (particularly those which are batch-processing oriented) allow the programmer to include control codes within a file to be printed, to control the vertical format of the printed page--for example, single/double line spacing, overprinting, and page ejection. A "print file" is one which includes such vertical format control ("VFC") information. There are three common ways for printer processes to determine VFC: CASE N: Non-Print File -------------- The file contains no VFC information. The printer process applies a standard format (e.g., single space, standard vertical margins) if the file is printed. CASE T: Print File with ASCII Format Effectors -------------------------------------- The file is "Telnet-like", containing the ASCII controls CR, LF, and FF to provide VFC. Braden
