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grep for minus (-) sign
Use flag "--" to stop switch parsing

Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by EVACopy http://evacopy.sourceforge.net

list block devices
Shows all block devices in a tree with descruptions of what they are.

Bash command to convert IP addresses into their "reverse" form

Synchronize both your system clock and hardware clock and calculate/adjust time drift
Do not run this command if you already have ntpd running! This needs to run as root, for example with sudo: $ sudo ntpdate pool.ntp.org && sudo hwclock --systohc && sudo hwclock --adjust This command will fetch accurate time from NTP servers and synchronize your system clock, then it will use the system clock to synchronize your hardware clock, and will calculate the time drift.

Print Memory Utilization Percentage For a specific process and it's children
Change the name of the process and what is echoed to suit your needs. The brackets around the h in the grep statement cause grep to skip over "grep httpd", it is the equivalent of grep -v grep although more elegant.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Convert a file from ISO-8859-1 (or whatever) to UTF-8 (or whatever)
I use it sometimes when I work on a french file transferred from a windows XP to a Debian-UTF8 system. Those are not correctly displayed: ? ? ? and so on $man tcs # for all charsets

list files by testing the ownership
Alternative to mnikhil's ls/awk solution

show each new entry in system messages as a popup
It willl popup a message for each new entry in /var/log/messages found on the notify-send howto page on ubuntuforums.org. Posted here only because it is one of the favourites of mine.


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