tunelp(8) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | FILES | NOTES | AVAILABILITY | COLOPHON

TUNELP(8)                 System Administration                TUNELP(8)

NAME         top

       tunelp - set various parameters for the lp device

SYNOPSIS         top

       tunelp [options] device

DESCRIPTION         top

       tunelp sets several parameters for the /dev/lp? devices, for
       better performance (or for any performance at all, if your
       printer won't work without it...) Without parameters, it tells
       whether the device is using interrupts, and if so, which one.
       With parameters, it sets the device characteristics accordingly.

OPTIONS         top

       -i, --irq argument
              specifies the IRQ to use for the parallel port in
              question.  If this is set to something non-zero, -t and -c
              have no effect.  If your port does not use interrupts,
              this option will make printing stop.  The command tunelp
              -i 0 restores non-interrupt driven (polling) action, and
              your printer should work again.  If your parallel port
              does support interrupts, interrupt-driven printing should
              be somewhat faster and efficient, and will probably be
              desirable.

              NOTE: This option will have no effect with kernel 2.1.131
              or later since the irq is handled by the parport driver.
              You can change the parport irq for example via
              /proc/parport/*/irq.  Read
              /usr/src/linux/Documentation/admin-guide/parport.rst for
              more details on parport.

       -t, --time milliseconds
              is the amount of time in jiffies that the driver waits if
              the printer doesn't take a character for the number of
              tries dictated by the -c parameter.  10 is the default
              value.  If you want fastest possible printing, and don't
              care about system load, you may set this to 0.  If you
              don't care how fast your printer goes, or are printing
              text on a slow printer with a buffer, then 500 (5 seconds)
              should be fine, and will give you very low system load.
              This value generally should be lower for printing graphics
              than text, by a factor of approximately 10, for best
              performance.

       -c, --chars characters
              is the number of times to try to output a character to the
              printer before sleeping for -t TIME.  It is the number of
              times around a loop that tries to send a character to the
              printer.  120 appears to be a good value for most printers
              in polling mode.  1000 is the default, because there are
              some printers that become jerky otherwise, but you must
              set this to `1' to handle the maximal CPU efficiency if
              you are using interrupts.  If you have a very fast
              printer, a value of 10 might make more sense even if in
              polling mode.  If you have a really old printer, you can
              increase this further.

              Setting -t TIME to 0 is equivalent to setting -c CHARS to
              infinity.

       -w, --wait milliseconds
              is the number of usec we wait while playing with the
              strobe signal.  While most printers appear to be able to
              deal with an extremely short strobe, some printers demand
              a longer one.  Increasing this from the default 1 may make
              it possible to print with those printers.  This may also
              make it possible to use longer cables.  It's also possible
              to decrease this value to 0 if your printer is fast enough
              or your machine is slow enough.

       -a, --abort <on|off>
              This is whether to abort on printer error - the default is
              not to.  If you are sitting at your computer, you probably
              want to be able to see an error and fix it, and have the
              printer go on printing.  On the other hand, if you aren't,
              you might rather that your printer spooler find out that
              the printer isn't ready, quit trying, and send you mail
              about it.  The choice is yours.

       -o, --check-status <on|off>
              This option is much like -a.  It makes any open(2) of this
              device check to see that the device is on-line and not
              reporting any out of paper or other errors.  This is the
              correct setting for most versions of lpd.

       -C, --careful <on|off>
              This option adds extra ("careful") error checking.  When
              this option is on, the printer driver will ensure that the
              printer is on-line and not reporting any out of paper or
              other errors before sending data.  This is particularly
              useful for printers that normally appear to accept data
              when turned off.

              NOTE: This option is obsolete because it's the default in
              2.1.131 kernel or later.

       -s, --status
              This option returns the current printer status, both as a
              decimal number from 0..255, and as a list of active flags.
              When this option is specified, -q off, turning off the
              display of the current IRQ, is implied.

       -r, --reset
              This option resets the port.  It requires a Linux kernel
              version of 1.1.80 or later.

       -q, --print-irq <on|off>
              This option sets printing the display of the current IRQ
              setting.

FILES         top

       /dev/lp?
       /proc/parport/*/*

NOTES         top

       -o, -C, and -s all require a Linux kernel version of 1.1.76 or
       later.

       -C requires a Linux version prior to 2.1.131.

AVAILABILITY         top

       The tunelp  command is part of the util-linux package and is
       available from Linux Kernel Archive 
       ⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩.

COLOPHON         top

       This page is part of the util-linux (a random collection of Linux
       utilities) project.  Information about the project can be found
       at ⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩.  If you
       have a bug report for this manual page, send it to
       util-linux@vger.kernel.org.  This page was obtained from the
       project's upstream Git repository
       ⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
       2020-12-18.  (At that time, the date of the most recent commit
       that was found in the repository was 2020-12-17.)  If you
       discover any rendering problems in this HTML version of the page,
       or you believe there is a better or more up-to-date source for
       the page, or you have corrections or improvements to the
       information in this COLOPHON (which is not part of the original
       manual page), send a mail to man-pages@man7.org

util-linux                    October 2011                     TUNELP(8)

Pages that refer to this page: lp(4)