Commands tagged perl (190)

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Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

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

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.

Localize provenance of current established connections
Sample command to obtain a list of geographic localization for established connections, extracted from netstat. Need geoiplookup command ( part of geoip package under CentOS)

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"

Fetch the Gateway Ip Address
Better use iproute2 !

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"

Show crontabs for all users
This is flatcaps tweaked command to make it work on SLES 11.2

va - alias for editing aliases
When setting up a new aliases file, or having creating a new file.. About every time after editing an aliases file, I source it. This alias makes editing alias a bit easier and they are useful right away. Note if the source failed, it will not echo "aliases sourced". Sub in vi for your favorite editor, or alter for ksh, sh, etc.

IFS - use entire lines in your for cycles
When you use a "for" construct, it cycles on every word. If you want to cycle on a line-by-line basis (and, well, you can't use xargs -n1 :D), you can set the IFS variable to .


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