Commands by dbh (9)

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List Listen Port by numbers
Show TCP Listen ports sorted by number (bugs: IPV6 addresses not supported)

shell function to make gnu info act like man.
I use this alias in my bashrc. The --vi-keys option makes info use vi-like and less-like key bindings.

Summarize Apache Extended server-status to show longest running requests
Ever need to know why Apache is bogging down *right now*? Hate scanning Apache's Extended server-status for the longest running requests? Me, too. That's why I use this one liner to quickly find suspect web scripts that might need review. Assuming the Extended server-status is reachable at the target URL desired, this one-liner parses the output through elinks (rendering the HTML) and shows a list of active requests sorted by longest running request at the bottom of the list. I include the following fields (as noted in the header line): Seconds: How long the request is alive PID: Process ID of the request handler State: State of the request, limited to what I think are the relevant ones (GCRK_.) IP: Remote Host IP making the request Domain: Virtual Host target (HTTP/1.1 Host: header). Important for Virtual Hosting servers TYPE: HTTP verb URL: requested URL being served. Putting this in a script that runs when triggered by high load average can be quite revealing. Can also capture "forgotten" scripts being exploited such as "formmail.pl", etc.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Set a user password without passwd
Slightly shorter. It doesn't create a subprocess either.

List all installed PERL modules by CPAN
This command will give you the detailed information about the installed perl modules i.e. installed path, Link type, version, files etc.

Fast tape rewind
Traditionally we rewind a tape using this syntaxis: $ mt -f /dev/rmt/0cbn rewind Redirecting the dispositive to nothing as shown above is faster. Less typing is always better.

Search $PATH for a command or something similar
Searches your $PATH for whatever you substitute for bash, though not sure if this will work if you substitute a different shell for bash!

Convert diff output to HTML ins/del

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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