Commands using ls (517)

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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.

Set gnome wallpaper to a random jpg from the specified directory
Every time this is run it will change your background picture. For added fun Add some DBUS magic: . $HOME/.dbus/session-bus/`cat /var/lib/dbus/machine-id`-0 export DBUS_SESSION_BUS_ADDRESS and a crontab entry: */5 * * * * above_command_in_script.sh >/dev/null 2>/dev/null now wallpaper changes every 5 mins

use SHIFT + ALT to toggle between two keyboard layouts
change the last two-character abbreviation to any layout abbreviation you want. This command will only run in the current session, add to your ~/.bashrc to make this permanent.

Run the Firefox Profile Manager
even when another instance is already open. Great for testing purposes when you need to be 2 people at once on the same site.

gawk gets fixed width field

Target a specific column for pattern substitution
Awk replaces every instance of foo with bar in the 5th column only.

Compare a remote file with a local file
Useful for checking if there are differences between local and remote files.

Automatically find and re-attach to a detached screen session
man screen: "-D -R Attach here and now. In detail this means: If a session is running, then reattach. If necessary detach and logout remotely first. If it was not running create it and notify the user. This is the author?s favorite."

grep for minus (-) sign
Use flag "--" to stop switch parsing

Insert the last argument of the previous command


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