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summarize a list of IP addresses, verifying IP address and giving counts for each IP found
Working with lists of IP addresses it is sometimes useful to summarize a count of how many times an IP address appears in the file. This example, summarizeIP, uses another function "verifyIP" previously defined in commandlinefu.com to ensure only valid IP addresses get counted. The summary list is presented in count order starting with highest count.

Print the contents of $VARIABLE, six words at a time
Print out the contents of $VARIABLE, six words per line, ignoring any single or double quotes in the text. Useful when $VARIABLE contains a sentence that changes periodically, and may or may not contain quoted text.

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.

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"

Tracklist reaplace backspace to '-'
Requires perl 5.14 or greater

lists files and folders in a folder
lists files and folders in a folder with summary.

Filter IP's in apache access logs based on use
The first sort is necessary for ips in a list to be actually unique.

For a $FILE, extracts the path, filename, filename without extension and extension.
Useful for use in other scripts for renaming, testing for extensions, etc.

Edit a file on a remote host using vim


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