Commands by jlaunay (16)

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Give to anyone a command to immediatly find a particular part of a man.
Example : $ LC_ALL=C man less | less +/ppattern

Delete all files older than X in given path
This will find all files under the path "." which are older than 10 days, and delete them. If you wish to use the "rm" command instead, replace "-delete" with "-exec rm [options] {} \;"

Convert flv without re-encoding

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

find sparse files
Prints the path/filename and sparseness of any sparse files (files that use less actual space than their total size because the filesystem treats large blocks of 00 bytes efficiently).

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" }

resume other user's screen session via su, without pty error
Normally, if you su to another user from root and try to resume that other user's screen session, you will get an error like "Cannot open your terminal '/dev/pts/0' - please check." This is because the other user doesn't have permission for root's pty. You can get around this by running a "script" session as the new user, before trying to resume the screen session. Note you will have to execute each of the three commands separately, not all on the same line as shown here. Credit: I found this at http://www.hjackson.org/blog/archives/2008/11/29/cannot-open-your-terminal-dev-pts-please-check.

Download Youtube video with wget!
Nothing special required, just wget, sed & tr!

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"

Find common groups between two users
Updated according to flatcap's suggestion, thanks!


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