Commands by jcoll (2)

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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" }

Terminal - Show directories in the PATH, one per line with sed and bash3.X `here string'

Graphically show percent of mount space used
Automatically drops mount points that have non-numeric sizes (e.g. /proc). Tested in bash on Linux and AIX.

connects to a serial console
e.g., 'screen -L /dev/ttyUSB0 38400' listens to your Holux M-241 GPS logger and turns on automatic logging

launch bash without using any letters
ry4an@four:~$ echo $SHLVL 1 ry4an@four:~$ ${0/-/} ry4an@four:~$ echo $SHLVL 2

Short Information about loaded kernel modules
I modify 4077 and marssi commandline to simplify it and skip an error when parsing the first line of lsmod (4077). Also, it's more concise and small now. I skip using xargs ( not required here ). This is only for GNU sed. For thoses without GNU sed, use that : $ modinfo $(lsmod | awk 'NR>1 {print $1}') | sed -e '/^dep/s/$/\n/g' -e '/^file/b' -e '/^desc/b' -e '/^dep/b' -e 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"

To get how many users logged in and logged out and how many times ?

Dump snapshot of UFS2 filesystem, then gzip it
Opens a snapshot of a live UFS2 filesystem, runs dump to generate a full filesystem backup which is run through gzip. The filesystem must support snapshots and have a .snap directory in the filesystem root. To restore the backup, one can do $ zcat /path/to/adXsYz.dump.gz | restore -rf -

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.


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