Commands by aysadk (101)

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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.

dstat- this command is powerful one to monitor system activity . It has combined the power of vmstat,iostat,mpstat,df,free,sar .
As mentioned in the summery that it is a powerful command to monitor system activity in great way. It has got the power of vmstat,iostat,mpstat,df,free and sar.Instead of firing each single command separately ,one can fire one single command to get all the info at once.But there is a way to get the individual information too. Please see the man page . You can get it from here : http://dag.wieers.com/home-made/dstat/

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" }

Force logout after 24 hours idle
Shell timeout variables (TMOUT) can be very liberal about what is classified as 'activity', like having an editor open. This command string will terminate the login shell for an user with more than a day's idle time.

Function to remove a directory from your PATH
Function to remove a specified path from your PATH environment variable.

creating you're logging function for your script
You could also pipe to logger.

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"

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

List just the executable files (or directories) in current directory
With zsh.

kill all foo process
Kill all processes with foo in them. Similar to pkill but more complete and also works when there is no pkill command. Works on almost every Linux/Unix platform I have tried.


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