Commands by peshay (11)

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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" }

get a directory from one machine to another using tar and ssh

Convert (almost) any video file into webm format for online html5 streaming
If you're using the experimental vorbis encoder (homebrew version of libffmpeg)

run a command whenever a file is touched
This is useful if you'd like to see the output of a script while you edit it. Each time you save the file the command is executed. I thought for sure something like this already exists - and it probably does. I'm on an older system and tend to be missing some useful things. Examples: $ ontouchdo yourscript 'clear; yourscript somefiletoparse' Edit yourscript in a separate window and see new results each time you save. $ ontouchdo crufty.html 'clear; xmllint --noout crufty.html 2>&1 | head' Keep editing krufty.html until the xmllint window is empty. Note: Mac/bsd users should use stat -f%m. If you don't have stat, you can use perl -e '$f=shift; @s=stat($f); print "$s[9]\n";' $1

backup local MySQL database into a folder and removes older then 5 days backups

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"

Generate SHA1 hash for each file in a list
All output is placed in file SHA1SUMS which you can later check with 'sha1sum --check'. Works on most Linux distros where 'sha1sum' is installed.

How to establish a remote Gnu screen session that you can re-connect to
Long before tabbed terminals existed, people have been using Gnu screen to open many shells in a single text terminal. Combined with ssh, it gives you the ability to have many open shells with a single remote connection using the above options. If you detach with "Ctrl-a d" or if the ssh session is accidentally terminated, all processes running in your remote shells remain undisturbed, ready for you to reconnect. Other useful screen commands are "Ctrl-a c" (open new shell) and "Ctrl-a a" (alternate between shells). Read this quick reference for more screen commands: http://aperiodic.net/screen/quick_reference

copy ACL of one file to another using getfacl and setfacl

Find installed network devices
Find installed network devices.


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