Commands by fotoflo (3)

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See multiple progress bars at once for multiple pipes with pv
In this example we convert a .tar.bz2 file to a .tar.gz file. If you don't have Pipe Viewer, you'll have to download it via apt-get install pv, etc.

Generate a random password 30 characters long
The pwgen program generates passwords which are designed to be easily memorized by humans, while being as secure as possible. Human-memorable passwords are never going to be as secure as completely completely random passwords. [from pwgen man page]

Add line number count as C-style comments
I often find the need to number enumerations and other lists when programming. With this command, create a new file called 'inputfile' with the text you want to number. Paste the contents of 'outputfile' back into your source file and fix the tabbing if necessary. You can also change this to output hex numbering by changing the "%02d" to "%02x". If you need to start at 0 replace "NR" with "NR-1". I adapted this from http://osxdaily.com/2010/05/20/easily-add-line-numbers-to-a-text-file/.

Watch and cat the last file to enter a directory
Great for watching things like Maildir's or any other queue directory.

Synchronize date and time with a server over ssh
If you are stuck behind a firewall and want to synchronize time with another server but you do not want to port forward NTP (which uses UDP) then this command is handy. It gets the time from a server and sets the local time. It is not that accurate but I can live with a second or so drift.

Pick a random line from a file

Search for classes in Java JAR files.

a function to put environment variable in zsh history for editing
This only makes sense if you are using command line editing. Create the function in your current zsh session, then type eve PATH go 'UP' in your history and notice the current (editable) definition of PATH shows up as the previous command. Same as doing: PATH="'$PATH'" but takes fewer characters and you don't have to remember the escaping.

Create a temporary file
To create directory, use: $ tempdir=$(/bin/mktemp -d)

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"


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