1GPSCAT(1)                     GPSD Documentation                     GPSCAT(1)
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NAME

6       gpscat - dump the output from a GPS
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SYNOPSIS

9       gpscat [-?] [--debug LVL] [--help] [--packetizer] [--speed SPEED]
10              [--typeflag] [--version] [-D LVL] [-h] [-p] [-s SPEED] [-t] [-V]
11              file-or-serial-port
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DESCRIPTION

14       gpscat is a simple program for logging and packetizing GPS data
15       streams. It takes input from a specified file or serial device
16       (presumed to have a GPS attached) and reports to standard output. The
17       program runs until end of input or it is interrupted by ^C or other
18       means. It does not terminate on a bad packet; this is intentional.
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20       In raw mode (the default) gpscat simply dumps its input to standard
21       output. Nonprintable characters other than ASCII whitespace are
22       rendered as hexadecimal string escapes.
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24       In packetizing mode, gpscat uses the same code as gpsd(8)'s packet
25       sniffer to break the input into packets. Packets are reported one per
26       line; line breaks in the packets themselves are escaped.
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28       This program is useful as a sanity checker when examining a new device.
29       It can be used as a primitive NMEA logger, but beware that (a)
30       interrupting it likely to cut off output in mid-sentence, and (b) to
31       avoid displaying incomplete NMEA sentences right up next to shell
32       prompts that often contain a $, raw mode always emits an extra final
33       linefeed.
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35       Also, be aware that packetizing mode will produce useless results —
36       probably consuming the entirety of input and appearing to hang — if it
37       is fed data that is not a sequence of packets of one of the known
38       types.
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40       The program accepts the following options:
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42       -?, -h, --help
43           Display program usage and exit.
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45       -D LVL, --debug LVL
46           In packetizer mode, enable progress messages from the packet
47           getter. Probably only of interest to developers testing packet
48           getter changes. Higher arguments to -D produce more output.
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50       -p, --packetizer
51           Invoke packetizer mode.
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53       -s SPEED, --speed SPEED
54           Set the port's baud rate (and optionally its parity and stop bits)
55           to SPEED before reading. Argument should begin with one of the
56           normal integer baud rates (300, 1200, 4800, 9600, 19200, 38400,
57           etc.). It may be followed by an optional suffix [NOE][12] to set
58           parity (None, Odd, Even) and stop bits (1 or 2).
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60           Specifying -s 4800N1 is frequently helpful with unknown devices.
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62       -t, --typeflag
63           Invoke packetizer mode, with the packet type and length (in
64           parentheses) reported before a colon and space on each line.
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66       -V, --version
67           Display program version and exit.
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SEE ALSO

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

74       Eric S. Raymond <esr@thyrsus.com>.
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78The GPSD Project                6 December 2020                      GPSCAT(1)