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8 min readConfiguring a wildcard SSL certificate involves the following steps:Purchase the certificate: Begin by acquiring a wildcard SSL certificate from a reliable Certificate Authority (CA). There are numerous CAs available, so choose based on your requirements and budget. Generate a Certificate Signing Request (CSR): The next step is to generate a CSR using your server software.
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5 min readThe "awk" command is a powerful tool used for text processing in the Bash shell. It is designed for scanning and processing text files, extracting data, and performing actions based on patterns. Here is an overview of how to use the "awk" command:Basic Syntax: The basic syntax of the "awk" command is as follows: awk '/pattern/ { action }' file.
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4 min readTo generate a 10-ms timer in Kotlin, you can use the Timer class provided by the Java standard library. Here's an example of how you can achieve this:Import the necessary libraries: import java.util.Timer import java.util.TimerTask Create a Timer object and a TimerTask object: val timer = Timer() val task = object : TimerTask() { override fun run() { // Code to be executed every 10 ms goes here } } Schedule the task to run repeatedly with a delay of 10 ms: timer.
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10 min readMutual TLS (mTLS) authentication is a method used to establish secure communication between a client and a server. Unlike traditional TLS authentication, where only the server is verified by the client, mTLS authentication requires both parties to authenticate each other using digital certificates.
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4 min readTo schedule tasks with cron in Bash, you can use the following steps:Open the crontab file using the command crontab -e. This will open the file in the default editor.Each line in the crontab file represents a task you want to schedule. Each task follows a specific syntax: Minute (0-59) Hour (0-23) Day of the month (1-31) Month (1-12) Day of the week (0-7, where both 0 and 7 represent Sunday) Command to be executed Choose the values for each field based on your desired schedule.
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9 min readRecursive type checking in Kotlin refers to the process of verifying and enforcing type safety in a situation where a class or interface is defined in terms of itself. This allows the creation of complex data structures or relationships that rely on recursive definitions.When checking the types of recursive declarations in Kotlin, the compiler employs a two-step process. First, it checks the base case(s) or terminal condition(s) that break the recursion.
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10 min readTo configure HTTPS for a load balancer, follow these steps:Obtain an SSL/TLS certificate: Before configuring HTTPS, you need to acquire an SSL/TLS certificate from a trusted certificate authority (CA). This certificate will ensure secure communication between the client and the load balancer. Install the SSL/TLS certificate: Once you have obtained the certificate, install it on the load balancer.
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7 min readAliases in Bash are used to create custom shortcuts or abbreviations for frequently used commands or command combinations. They allow users to define their own easy-to-remember names for complex or lengthy commands.Creating an alias in Bash involves using the alias command followed by a chosen name (usually in lowercase) and the command or commands it represents, enclosed in quotes.
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5 min readParsing a PDF in Kotlin can be achieved using external libraries such as Apache PDFBox or iText. Here's a step-by-step guide on how to parse a PDF using Apache PDFBox in Kotlin:First, ensure that you have added the required dependency for Apache PDFBox in your Kotlin project. You can do this by including the following line in your build.gradle file: implementation 'org.apache.pdfbox:pdfbox:2.0.
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7 min readTo configure a custom SSL cipher suite, you need to follow these steps:Identify the SSL/TLS library or server that you are using. Popular options include OpenSSL, Microsoft IIS, and Apache HTTP Server.Understand the format and syntax used by the particular SSL/TLS library or server configuration file.Determine the cipher suites you want to include in your custom suite. A cipher suite is a combination of encryption algorithms, key exchange methods, and message authentication codes (MACs).
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4 min readWildcards are special characters that can be used in Bash programming to match multiple files or directories with similar names. They provide a convenient way to perform operations on multiple files at once.Here are some commonly used wildcards in Bash:Asterisk (*) wildcard: Matches any sequence of characters, including no characters. For example, *.txt will match all files with a .txt extension in the current directory. Question mark (?) wildcard: Matches any single character.