Function print_device

backend/usb-libusb.c:168–684

 */

int					/* O - Exit status */
print_device(const char *uri,		/* I - Device URI */
             const char *hostname,	/* I - Hostname/manufacturer */
             const char *resource,	/* I - Resource/modelname */
	     char       *options,	/* I - Device options/serial number */
	     int        print_fd,	/* I - File descriptor to print */
	     int        copies,		/* I - Copies to print */
	     int	argc,		/* I - Number of command-line arguments (6 or 7) */
	     char	*argv[])	/* I - Command-line arguments */
{
  int	        bytes;			/* Bytes written */
  ssize_t	total_bytes;		/* Total bytes written */
  struct sigaction action;		/* Actions for POSIX signals */
  int		status = CUPS_BACKEND_OK,
					/* Function results */
		iostatus;		/* Current IO status */
  pthread_t	read_thread_id,		/* Read thread */
		sidechannel_thread_id;	/* Side-channel thread */
  int		have_sidechannel = 0,	/* Was the side-channel thread started? */
		have_backchannel = 0;   /* Do we have a back channel? */
  struct stat   sidechannel_info;	/* Side-channel file descriptor info */
  unsigned char	print_buffer[8192],	/* Print data buffer */
		*print_ptr;		/* Pointer into print data buffer */
  fd_set	input_set;		/* Input set for select() */
  int		nfds;			/* Number of file descriptors */
  int		nfd_max;		/* Maximum file descriptor number for select() */
  struct timeval *timeout,		/* Timeout pointer */
		tv;			/* Time value */
  struct timespec cond_timeout;		/* pthread condition timeout */
  int		num_opts;		/* Number of options */
  cups_option_t	*opts;			/* Options */
  const char	*val;			/* Option value */
  char		dummy;			/* select() wakeup bogus data */


  load_quirks();

 /*
  * See if the side-channel descriptor is valid...
  */

  have_sidechannel = !fstat(CUPS_SC_FD, &sidechannel_info) &&
                     S_ISSOCK(sidechannel_info.st_mode);

 /*
  * Create a pipe for waking up the main thread from select()...
  */

  if (pipe(g.wakeup_pipe) < 0)
  {
    fprintf(stderr, "DEBUG: Unable to create wakeup pipe - %s\n",
	    strerror(errno));
    return (CUPS_BACKEND_STOP);
  }

  g.wait_eof = WAIT_EOF;

 /*