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calulate established tcp connection of local machine
If you want prepend/append text just wrap in echo: $echo Connected: `netstat -an|grep -ci "tcp.*established"`

Monitor a file with tail with timestamps added

random xkcd comic
i sorta stole this from http://www.shell-fu.org/lister.php?id=878#MTC_form but it didn't work, so here it is, fixed. --- updated to work with jpegs, and to use a fancy positive look behind assertion.

Show some trivia related to the current date
Contrary to logic, typing calendar won't show a calendar, that's the job of cal. Typing calendar will show some trivia related to the current date. Tested against many Linux distros and FreeBSD.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

umount --rbind mount with submounts
Original: https://bugzilla.redhat.com/show_bug.cgi?id=194342

Find longest running non-root processes on a machine
If you have ever been trying to look for a list of processes based on their elapsed time you don't need to look any further. This command lets you find the list of processes ordered in a reversed order (oldest at the top) that have been running for over an hour on your system. Any system processes are filtered out, leaving only user initiated ones in. I find it extremely useful for debugging and performance analysis.

Verbosely delete files matching specific name pattern, older than 15 days.

Watch active calls on an Asterisk PBX
This handles when you have a single call or channel. Other commands will strip out the result if there is a single channel or call active because the output changes the noun to be singular instead of plural.

Insert a line at the top of a text file without sed or awk or bash loops
Yet another way to add a line at the top a of text file with the help of the tac command (reverse cat).


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