sethrh

# Program to test for a race condition in rostopic handlers
# Run (note the single & to put the first pub in the background and simultaneously start the second)
# $ rostopic pub -1 /test_topic1 std_msgs/String "data: 'hello1'" & rostopic pub -1 /test_topic2 std_msgs/String "data: 'hello2'"
# Both topic handlers should fire nearly simultaenously. 
# Each topic reads the global variable, then increments it by 1. 
# When one thread increments the GLOBAL from 1 to 3, you have a race condition. 

import rospy
from std_msgs.msg import String
import threading

sethrh

import datetime 

def utcnow():
    """Return a timezone-aware now, in UTC.
    """
    return datetime.datetime.now(datetime.timezone.utc)


def tznow():
    """Return a timezone-aware now, in the local timezone.

sethrh

# SRH 17-Mar-2021
"""
Improved os.path.splitext which properly deals with files containing multiple
dots in extensions.
"""

import os


def better_splitext(name):

sethrh

'''
To run:
$ python3.7 -m venv txaio-test
$ . txaio-test/bin/activate
(txaio-test) $ pip install txaio
Collecting txaio
  Downloading https://files.pythonhosted.org/packages/4f/82/0cd8d81d57e55a598cd4cef10c6e971dbcaf437e4f138dc1624cf7c1388e/txaio-20.4.1-py2.py3-none-any.whl
Installing collected packages: txaio
Successfully installed txaio-20.4.1
(txaio-test) $ python txaio-test.py

sethrh

a = 55
b = 99

print(a)
print(a & b, hex(a & b), bin(a & b))
print(a | b, hex(a | b), bin(a | b))
print(a ^ b, hex(a ^ b), bin(a ^ b))

a = 'abcdefgh'[:2]
x = 0x7F7F

sethrh

#!/bin/bash
# Shell script to run rdiff-backup. 
# Put this in your crontab to run this every hour: 
# 0 * * * * /home/seth/root/bin/backup.sh

# Change these locations to suit
BACKUP_DIR=/opt/backup/$HOSTNAME
BACKUP_LOG=$HOME/backup.log

savelog -n -c 7 "$BACKUP_LOG"

sethrh

import os
from django.core.wsgi import get_wsgi_application
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "your-project.settings")
application = get_wsgi_application()


try:
    import uwsgi
    from uwsgidecorators import timer
    from django.utils import autoreload

sethrh

def multifilter(seq, *tests, multiple=False):
    """Filters items in a list into sublists corresponding to the
    supplied test functions.

    :returns: A list of lists of items matching conditions, in order. The last
              item in the return value is the list of items that did not
              match any condition.

            [[items matching condition0],
             [items matching condition1],

sethrh

#!/Library/Frameworks/Python.framework/Versions/3.4/bin/python3
"""
Synchronously call an asyncio task/coroutine from a non-asyncio thread. 

usage: 
    # block the current thread until the coroutine yields or returns
    value = sync_call(loop, coroutine, 1, 2, 3, four=4, five=5)
    # control returns here when the coroutine is done
"""
import asyncio

sethrh

from functools import wraps
from threading import Condition

"""
Usage: 

cond = Condition()

Acquire the condition, wait for it, then do something: 
@WaitOn(cond)