Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages


home | help
GPSCAT(1)		      GPSD Documentation		     GPSCAT(1)

       gpscat -	dump the output	from a GPS

       gpscat [-s speed] [-p] [-t] [-D debuglevel] file-or-serial-port

       gpscat is a simple program for logging and packetizing GPS data
       streams.	It takes input from a specified	file or	serial device
       (presumed to have a GPS attached) and reports to	standard output. The
       program runs until end of input or it is	interrupted by ^C or other
       means. It does not terminate on a bad packet; this is intentional.

       In raw mode (the	default) gpscat	simply dumps its input to standard
       output. Nonprintable characters other than ASCII	whitespace are
       rendered	as hexadecimal string escapes.

       In packetizing mode, gpscat uses	the same code as gpsd(8)'s packet
       sniffer to break	the input into packets.	Packets	are reported one per
       line; line breaks in the	packets	themselves are escaped.

       This program is useful as a sanity checker when examining a new device.
       It can be used as a primitive NMEA logger, but beware that (a)
       interrupting it likely to cut off output	in mid-sentence, and (b) to
       avoid displaying	incomplete NMEA	sentences right	up next	to shell
       prompts that often contain a $, raw mode	always emits an	extra final

       Also, be	aware that packetizing mode will produce useless results --
       probably	consuming the entirety of input	and appearing to hang -- if it
       is fed data that	is not a sequence of packets of	one of the known

       The program accepts the following options:

	   Invoke packetizer mode.

	   Set the port's baud rate (and optionally its	parity and stop	bits)
	   before reading. Argument should begin with one of the normal
	   integer baud	rates (300, 1200, 4800,	9600, 19200, 38400, etc.). It
	   may be followed by an optional suffix [NOE][12] to set parity
	   (None, Odd, Even) and stop bits (1 or 2).

	   Invoke packetizer mode, with	the packet type	and length (in
	   parentheses)	reported before	a colon	and space on each line.

	   In packetizer mode, enable progress messages	from the packet
	   getter. Probably only of interest to	developers testing packet
	   getter changes. Higher arguements to	D produce more output.

	   Display program usage and exit.

       Specifying -s 4800N1 is frequently helpful with unknown devices.

       gpsd(8),	gps(1),	libgps(3), libgpsmm(3),	gpsfake(1).  gpsprof(1),
       gpsctl(1), gpsdctl(8), gpsmon(1).

       Eric S. Raymond <>.

The GPSD Project		  16 Nov 2006			     GPSCAT(1)


Want to link to this manual page? Use this URL:

home | help