MANSFIELD@DHDEMBL5.BITNET (Niall Mansfield) (03/12/86)
Subj: Tektronix emulation, Laser printers and VMS Last november, johnston@lbl-csam said > Reguarding the problems of sending Tektronix 40xx Graph Mode > files out over VMS serial lines .... > > You have run into what I consider to be a classic problem with > VMS. VMS has a highly structured notion of what are files, async > terminals, parallel output devices, etc.. One result of this is > that the notion of record boundaries is ingrained at the lowest > levels of software (the I/O device drivers) and sometimes in the > devices themselves. Without rewriting the device driver for the, > say DMF32 serial lines, it is not possible to get more than 511 > (if I recall, though some devices go to 65K) bytes out with out a > line feed being inserted by the device driver. I don't believe this. I sent 1.2 million chars to a terminal and as far as I can make out no linefeed or carriage return was sent. The terminal was set to NOWRAP; the program was written in C, and just did 1.2 million putchar()'s. What might account for this idea is that if you use standard VAX utilities like COPY, TYPE, etc, THEY do indeed seem to have strong views that files consist of records (and records can contain characters if they feel like it), and will often transmit a linefeed at the end of (what they believe to be) a "record". > ... I will not be drawn into any religious discussions. I will.