Unix / Linux: Count Files in Directory
Objective: Count the number of files in a directory on Unix or Linux.
Unix / Linux: Print IO Statistics of Running dd Process
Let’s say you have a dd process that is running. By default, dd will only print IO statistics once the job has been completed or if it is interrupted by a Ctrl-C (SIGINT) command. While the job is running, you will probably have no idea how much data has been copied, the current progress or the copying speed. But fret not, there is actually a way to get the IO statistics of a running dd process.
Android: ADB – List Installed Package Names
Objective: List all the installed packages on an Android phone through an ADB shell.
Shell Script: Convert Uppercase to Lowercase
Objective: Convert the contents of a file or the contents of a shell string variable from uppercase to lowercase.
Unix / Linux: Backup Restore Partition Table (MBR, EBR)
The partition table are most commonly associated with the Master Boot Record (MBR) and Extended Boot Record (EBR) on x86 systems. They are both 512 bytes long.
Unix / Linux: Sync Local Directories
To sync files between two local directories on Unix or Linux, you can either choose to perform a soft link to the source directory or use rsync or lsyncd daemon.
MySQL: Export Each Database to Individual SQL File
MySQL backups are normally done using mysqldump – a MySQL database backup program. The problem is all the backups will be written to a single output SQL file. I prefer to dump each MySQL database to a separate SQL file.
Shell Script: Check If Weekday
There are two ways to perform a “is it a weekday” logic in shell scripts. One way is to use cron. The other is to get the day of week from the date command.
Unix / Linux: Generate MD5 Checksum
The md5sum command can be used to generate MD5 checksums for a string or a file. This is installed by default on most Unix and Linux distributions.
Disable Nginx Version Number in HTTP Headers
By default, Nginx sends the version number in the HTTP response. Hackers can use this information to try and exploit any known vulnerabilities in Nginx, especially if you are running a version with known vulnerabilities. Security wise, it’s a good practice to not reveal versions numbers of the HTTP server.
