lp(7) Miscellaneous Information Manual lp(7)
NAME
lp - line printer
SYNOPSIS
Remarks
This manual entry applies only to a certain group of printers. For Series 800, it applies to printers controlled by the device driver It
does apply to any printers on Series 700 systems.
DESCRIPTION
This section describes capabilities provided by many line printers supported by various versions of the HP-UX operating system. A line
printer is a character special device that may optionally have an interpretation applied to the data.
If the character special device file has been created with the raw option (see the HP-UX System Administrator manuals for information about
creating device files with the raw option), data is sent to the printer in (as, for example, when handling a graphics printing operation).
In raw mode, no interpretation is done on the data to be printed, and no page formatting is performed. Data bytes are simply sent to the
printer and printed exactly as received.
If the device file does not contain the raw option, data can still be sent to the printer in raw mode. Raw mode is set and cleared by the
request.
If the line printer device file does not contain the raw option, data is interpreted according to rules discussed below. The driver under-
stands the concept of a printer page in that it has a page length (in lines), line length (in characters), and offset from the left margin
(in characters). The default line length, indent, lines per page, open and close page eject, and handling of backspace are set to defaults
determined when the printer is opened and recognized by the system the first time. If the printer is not recognized, the default line
length is 132 characters, indent is 4 characters, lines per page is 66, one page is ejected on close and none on open, and backspace is
handled for a character printer.
The following rules describe the interpretation of the data stream:
o A form feed causes a page eject and resets the line counter to zero.
o Multiple consecutive form-feeds are treated as a single form-feed.
o The new-line character is mapped into a carriage-return/line-feed sequence, and if an offset is specified a number of blanks are
inserted after the carriage-return/line-feed sequence.
o A new-line that extends over the end of a page is turned into a form-feed.
o Tab characters are expanded into the appropriate number of blanks (tab stops are assumed to occur every eight character positions
as offset by the current indent value).
o Backspaces are interpreted to yield the appropriate overstrike either for a character printer or a line printer.
o Lines longer than the line length minus the indent (i.e., 128 characters, using the above defaults) are truncated.
o Carriage-return characters cause the line to be overstruck.
o When it is opened or closed, a suitable number of page ejects is generated.
Two ioctl(2) requests are available to control the lines per page, characters per line, indent, handling of backspaces, and number of pages
to be ejected at open and close times. At either open or close time, if no page eject is requested the paper will not be moved. For
opens, line and page counting will start assuming a top-of-form condition.
The ioctl requests have the following form:
The possible values of request are:
Get the current printer status information and store in the
structure to which arg points.
Set the current printer status information from the structure to which
arg points.
The structure used in the and requests is defined in and includes the following members:
short int ind; /* indent */
short int col; /* columns per page */
short int line; /* lines per page */
short int bksp; /* backspace handling flag */
short int open_ej; /* pages to eject on open */
short int close_ej; /* pages to eject on close */
short int raw_mode; /* raw mode flag */
These are remembered across opens, so the indent, page width, and page length can be set with an external program. If the field is set to
zero, the defaults are restored at the next open.
If the backspace handling flag is 0, a character printer is assumed and backspaces are passed through the driver unchanged. If the flag is
a 1, a line printer is assumed, and sufficient print operations are generated to generate the appropriate overstruck characters.
If the raw mode flag is 0, data sent to the printer is formatted according to indent, columns per page, lines per page, backspace handling,
and pages to eject on open and close.
If the raw mode flag is 1, data sent to the printer is not formatted.
If the raw mode flag is changed from 1 to 0 (raw mode is turned off) and the format settings (indent, columns per page, etc.) have not
been modified, the data is formatted according to the prior format settings.
AUTHOR
was developed by HP and AT&T.
FILES
default or standard printer used by some HP-UX commands;
special files for printers
SEE ALSO
lp(1), slp(1), ioctl(2), cent(7), intro(7).
Seires 800 Only lp(7)