@node _bios_printer, bios
@subheading Syntax

@example
#include <bios.h>

unsigned _bios_printer(unsigned cmd, unsigned printer, unsigned data);
@end example

@subheading Description
The _bios_printer routine uses INT 0x17 to perform printer output
services for parallel printers. The @var{printer} argument specifies
the affected printer, where 0 is LPT1, 1 is LPT2, and so on.
The @var{cmd} argument can be any of the following manifest
constants:

@table @code

@item _PRINTER_INIT

@item Reset and initialize the specified printer port

@item _PRINTER_STATUS

Return the status of the specified printer port

@item _PRINTER_WRITE

Print the @var{data} argument to the specified printer port

@end table

@subheading Return Value

The _bios_printer function returns the value in the AX register
after the BIOS interrupt. The high-order byte (AH) of the return
value indicates the printer status after the operation, as defined
below:

@example
Bit     Meaning if True

0       Printer timed out
1       Not used
2       Not used
3       I/O error
4       Printer selected
5       Out of paper
6       Acknowledge
7       Printer not busy
@end example

@subheading Portability

@portability !ansi, !posix

@subheading Example

@example
while (*c)
  _bios_printer(_PRINTER_WRITE, *c++, 0);
@end example