I am reading some data from gpsd and writing it using using Python's logging module. I am fairly confident that only one process writes to this file, although I read from it using tail while this logger is running. Every once in a while I am seeing some log entries that look like the image below. I am hoping that somebody can shed some light on what would cause (presumably Python) to insert null control characters into my log file.
The code I am using is:
"""
Read the GPS continuously
"""
import logging
from logging.handlers import RotatingFileHandler
import sys
import gps
LOG = '/sensor_logs/COUNT.csv'
def main():
log_formatter = logging.Formatter('%(asctime)s,%(message)s', "%Y-%m-%d %H:%M:%S")
my_handler = RotatingFileHandler(LOG, mode='a', maxBytes=1024*1024,
backupCount=1, encoding=None, delay=0)
my_handler.setFormatter(log_formatter)
my_handler.setLevel(logging.INFO)
app_log = logging.getLogger('root')
app_log.setLevel(logging.INFO)
app_log.addHandler(my_handler)
session = gps.gps("localhost", "2947")
session.stream(gps.WATCH_ENABLE | gps.WATCH_NEWSTYLE)
while True:
try:
report = session.next()
if hasattr(report, 'gdop'):
satcount = 0
for s in report['satellites']:
if s['used'] == True:
satcount+=1
data = "{}".format(str(satcount))
app_log.info(data)
except KeyError:
pass
except KeyboardInterrupt:
quit()
except StopIteration:
session = None
if __name__ == "__main__":
main()
This ended up being a result of failing hardware. Thank you for your help, @RobertB.