capsprninfo.c File Reference

A command line tool to retrieve some information about his printer device. More...

Data Structures
struct	ieee1284_id

Macros
#define	IOCTL_IEEE1284_ID_GET(cnt)   _IOC(_IOC_READ, 'P', 1, cnt)
#define	IOCTL_PRINTER_RESET   _IOC(_IOC_NONE, 'P', 7, 0)

Functions
static int	_prn_info_ieee_id_print (int fd)
static int	_prn_info_status_print (int fd)
static int	_prn_info_printer_reset (int fd)
static void	handle_nls (void)
static void	print_help (FILE *out)
int	main (int argc, char **argv)

Variables
static int	verbose
static const struct option	long_options []

Detailed Description

Copyright

GNU Lesser General Public License 2.1

Author

Jürgen Borleis

Warning

Use as experimental

Macro Definition Documentation

IOCTL_IEEE1284_ID_GET

#define IOCTL_IEEE1284_ID_GET

(

cnt

)

_IOC(_IOC_READ, 'P', 1, cnt)

IOCTL_PRINTER_RESET

#define IOCTL_PRINTER_RESET   _IOC(_IOC_NONE, 'P', 7, 0)

Function Documentation

_prn_info_ieee_id_print()

static int _prn_info_ieee_id_print ( int  fd )

static

Retrieve printer's IEEE1284 ID and print it to stdout

Parameters

[in]

fd

The printer's corresponding device node

Return values

0	Successful
Negative	errno else

Don't know why the kernel does not export this IOCTL command. We need a '1' command to retrieve the IEEE1284 ID and a so called 'new' style IOCTL.

Note

In the returned IEEE1284 ID data set, a 16 bit count value in big endian notation leads the string and defines the whole size of the data including itself.

_prn_info_status_print()

static int _prn_info_status_print ( int  fd )

static

Retrieve the printer's status and print a decoded list

Parameters

[in]

fd

The printer's corresponding device node

Return values

0	Successful
Negative	errno else

The kernel expands a signed char into an signed int. Thus, we recice a 0xffffffb0 if the printer is busy and out of paper.

_prn_info_printer_reset()

static int _prn_info_printer_reset ( int  fd )

static

Reset the printer ('soft' style)

Parameters

[in]

fd

The printer's corresponding device node

Return values

0	Successful
Negative	errno else

Don't know why the kernel does not export this IOCTL command. We need a '7' (e.g. IOCNR_SOFT_RESET) command to trigger a soft reset and a so called 'new' style IOCTL.

handle_nls()

static void handle_nls ( void  )

static

print_help()

static void print_help ( FILE *  out )

static

main()

int main	(	int	argc,
		char **	argv
	)

Variable Documentation

verbose

int verbose

static

long_options

const struct option long_options[]

static

Initial value:

= {
    { .name = "verbose", .has_arg = no_argument, .val = 'v', },
    { .name = "help", .has_arg = no_argument, .val = 'h', },
    { .name = NULL, },
}