Commands by mathias (5)

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Always tail/edit/grep the latest file in a directory of timestamped files
zsh only If you have this command in your history, you can always re-run it and have it reference the latest file. The glob matches all timestamped files and then the resulting array is sorted by modification time (m) and then the first element in the sorted array is chosen (the latest)

Install pip with Proxy
Installs pip packages defining a proxy

Then end of the UNIX epoch
http://en.wikipedia.org/wiki/Year_2038_problem Some other notable dates that have passed: $ date -d@1234567890 $ date -d@1000000000

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"

ensure your ssh tunnel will always be up (add in crontab)
I find it ugly & sexy at the same time isn't it ?

Apply fade effect to a audio
fade [type] fade-in-length [stop-time [fade-out-length]] Apply a fade effect to the beginning, end, or both of the audio. An optional type can be specified to select the shape of the fade curve: q for quarter of a sine wave, h for half a sine wave, t for linear (`triangular') slope, l for logarithmic, and p for inverted parabola. The default is logarithmic. A fade-in starts from the first sample and ramps the signal level from 0 to full volume over fade-in-length sec? onds. Specify 0 seconds if no fade-in is wanted. For fade-outs, the audio will be truncated at stop-time and the signal level will be ramped from full volume down to 0 starting at fade-out-length seconds before the stop-time. If fade-out-length is not specified, it defaults to the same value as fade-in-length. No fade-out is performed if stop-time is not specified. If the file length can be determined from the input file header and length-changing effects are not in effect, then 0 may be specified for stop-time to indicate the usual case of a fade-out that ends at the end of the input audio stream. All times can be specified in either periods of time or sample counts. To specify time periods use the format hh:mm:ss.frac format. To specify using sample counts, specify the number of samples and append the letter `s' to the sample count (for example `8000s').

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Clear terminal Screen
Probably the quickest / easiest way to clear the screen.

back ssh from firewalled hosts
host B (you) redirects a modem port (62220) to his local ssh. host A is a remote machine (the ones that issues the ssh cmd). once connected port 5497 is in listening mode on host B. host B just do a ssh 127.0.0.1 -p 5497 -l user and reaches the remote host'ssh. This can be used also for vnc and so on.

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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