Commands tagged firewall (8)

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check open ports without netstat or lsof

check open ports without netstat or lsof

for all flv files in a dir, grab the first frame and make a jpg.
This is handy for making screenshots of all your videos for referring to in your flv player.

Wait for file to stop changing
Here's a way to wait for a file (a download, a logfile, etc) to stop changing, then do something. As written it will just return to the prompt, but you could add a "; echo DONE" or whatever at the end. This just compares the full output of "ls" every 10 seconds, and keeps going as long as that output has changed since the last interval. If the file is being appended to, the size will change, and if it's being modified without growing, the timestamp from the "--full-time" option will have changed. The output of just "ls -l" isn't sufficient since by default it doesn't show seconds, just minutes. Waiting for a file to stop changing is not a very elegant or reliable way to measure that some process is finished - if you know the process ID there are much better ways. This method will also give a false positive if the changes to the target file are delayed longer than the sleep interval for any reason (network timeouts, etc). But sometimes the process that is writing the file doesn't exit, rather it continues on doing something else, so this approach can be useful if you understand its limitations.

Limit the transfer rate and size of data over a pipe
This example will close the pipe after transferring 100MB at a speed of 3MB per second.

rot13 simple substitution cipher via command line
E.g. Useful for hiding spoilers in reviews, etc.

shell function which allows you to tag files by creating symbolic links directories in a 'tags' folder.
The tag function takes a tag name as its first argument, then a list of files which take that tag. The directory $HOME/tags/tagname will then hold symbolic links to each of the tagged files. This function was inspired by tmsu (found at https://bitbucket.org/oniony/tmsu/wiki/Home). Example: $ tag dog airedale.txt .shizturc weimeraner.pl This will create $HOME/tags/dog which contains symbolic links to airedale.txt .shizturc and weimeraner.pl

Read almost everything (Changelog.gz, .tgz, .deb, .png, .pdf, etc, etc....)
It allows customizing by means of lesspipe. You need to write a ~/.lessfilter script and put this into your ~/.bashrc: eval $(lesspipe) export LESS=-r

Install pip with Proxy
Installs pip packages defining a proxy

Compare directories via diff
http://hints.macworld.com/article.php?story=20070408062023352


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