Linux: Get Time in Timezone
Explains how to get the current time in a different timezone on Linux without changing the system timezone.
Unix / Linux: Run Sudo Without Password
Explains how to run sudo commands without a password on Unix and Linux systems by modifying the sudoers configuration file.
Linux: Pretty Print Mount Output
Explains how to pretty print the output of the mount command on Linux by formatting the output using printf, awk and column commands.
Linux: SSH Session Logging
Explains how to perform ssh session logging on Linux using tee and screen commands.
Linux: Make File Undeletable / Immutable
Explains how to make a file undeletable or immutable on Linux using extended file attributes. Even a root user will not be able to delete a file with the immutable attribute set.
Linux: Get SSL Certificate Expiration Date
Explains how to get the expiration date of a SSL certificate for a domain on Linux from the command line using openssl.
Linux: Get Subject Alternative Name (SAN) from SSL Certificate
Explains how to print the Subject Alternative Name (SAN) field from a SSL certificate on a server or from a certificate file using openssl.
Unix / Linux: Concatenate Multiple Files
Learn how to concatenate multiple text or binary files into a single file on Unix / Linux. Also learn how to append the contents of a file to the end of another file or concatenate the same file to itself multiple times.
How to Decrypt WhatsApp crypt12 Database Messages
Decrypt WhatsApp crypt12 database files with a simple Java program.
Unix / Linux: Find and Delete Zero Byte Files
Explains how to find and delete zero byte size files using the find command on Unix and Linux. Also explains how to delete files only in the current directory using maxdepth and prune options.
