In Python, How Do You Call a Function as a New Thread with the threading Module?

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Problem scenario
(The old problem scenario was “You want to write a program to call a unbound function in a new thread with the threading module. How do you do this?”)

You want to write a program to call a function in a new thread with the threading module. How do you do this?

Solution
Run this program (e.g.,

…

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How Do You Get a PHP Program to Invoke a Python Program via Browsing a Website?

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Problem scenario
You want Debian/Ubuntu Linux to support a website. You want a Python program to run every time a web page is downloaded. How do you get a PHP program to invoke a Python program on Debian/Ubuntu Linux?

Solution

Prerequisites
i. This assumes you have Apache2 and PHP installed. If you need assistance run this: sudo apt -y install apache2 php
ii.

…

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How Do You Read in User Input with Golang?

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Problem scenario
You want to read in user input with Golang. What should you do?

Solution
This program will illustrate how you accept user input with a Golang program:

package main

import (
“bufio”
“fmt”
“os”
)

func main() {
fmt.Println(“Please enter some text:”)
reader := bufio.NewReader(os.Stdin)
text, _ := reader.ReadString(‘\n’)
fmt.Println(“The text you entered was this: “, text)
} …

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How Do You Install Firefox on a Windows Server with PowerShell?

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Problem scenario
You want to install Firefox on a Windows server without using the traditional GUI method. What should you do?

Solution
Updated on 5/16/21
1. Open PowerShell ISE as Administrator (right click it, go to More -Run as Administrator).
2. Run this script (e.g., firefox.ps1):

# This script was mostly taken from https://forum.pulseway.com/topic/1940-install-firefox-with-powershell/

# www.continualintegration.com changed the version number of Firefox and added some comments
# Silent Install Firefox

# Download URL: https://www.mozilla.org/en-US/firefox/all/

# Path for the workdir
$workdir = “c:\installer\”

# Check if work directory exists if not create it

If (Test-Path -Path $workdir -PathType Container)
{ Write-Host “$workdir already exists” -ForegroundColor Red}
ELSE
{ New-Item -Path $workdir -ItemType directory }

# Download the installer

$source = “https://download.mozilla.org/?product=firefox-88.0.1-SSL&os=win64&lang=en-US”
$destination = “$workdir\firefox.exe”

# Check if Invoke-Webrequest exists otherwise execute WebClient

if (Get-Command ‘Invoke-Webrequest’)
{
Invoke-WebRequest $source -OutFile $destination
}
else
{
$WebClient = New-Object System.Net.WebClient
$webclient.DownloadFile($source, …

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How Do You Troubleshoot an Error Such as “UnboundLocalError: local variable ‘foobar’ referenced before assignment”?

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Problem scenario
You run a Python program. You receive this message: “UnboundLocalError: local variable ‘foobar’ referenced before assignment”

What should you do?

Solution
Initialize the variable (e.g., foobar = 0). If you do so inside a function wherein foobar is called, that may work. If you want it to be available globally throughout your program, you will initialize it outside of a function.

…

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How Do You Troubleshoot Golang Using Hexademical Values?

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Problem scenario
Your Golang program has variables with values that look like this:

{0xc4200457e8 [97 49]}

You think the that underlying variables should have regular alphabetic string values. What should you do?

Solution
Use the .string() function.

When you use strings.Builder for a variable, the value will be a hexadecimal value. To retrieve the string value that you intend,

…

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How Do You Troubleshoot the Golang Error “missing function body”?

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Problem scenario
You run a Golang program with a function that uses a map. You get this error:

./foobar.go:33:6: missing function body
./foobar.go:33:44: syntax error: unexpected {, expecting comma or )

What should you do?

Solution
Omit the “{}” in passing map data types to the function. The syntax for declaring a map will include {}.

Here is an example of how to properly define a map:

goodmap := map[string][5]string{}

But when you are defining a function that will accept a map as a parameter,

…

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How Do You Write a Python Program to Create New Processes with the multiprocessing Library?

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Problem scenario
You want to create new processes with the multiprocessing library in Python. What should you do?

Solution
Run this program:

“”” In a duplicate terminal window, run this command before, during and after you run the pyhon script: sudo ps -ef | grep python | wc -l

The integer that returns will go up by two showing a new processes have been created when the program is still running. …

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How Do You Write a Tic-Tac-Toe Program in Golang?

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Problem scenario
You want to play TicTacToe. You have a Golang compiler installed. What should you do?

Solution
Prerequisites
This assumes that you have installed Go. If you need assistance, see this posting.

Procedures
1. Name this program tictactoe.go.

package main

import (
“strings”
“bufio”
“fmt”
“os”
)

func mapper(letter string) int{
if strings.TrimRight(letter, …

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