Commands by drizztbsd (1)

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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"

Delete all empty lines from a file with vim
If you need to delete lines that may contain space characters (such as tabs or spaces) as well as empty ones, try: $:v/\S/d Just an alternative.

GZip all files in a directory separately
It gzip each file in a directory separately

Find dupe files by checking md5sum

Using bash inline
There are two ways to use "here documents" with bash to fill stdin: The following example shows use with the "bc" command. a) Using a delimiter at the end of data: $ less-than less-than eeooff bc > k=1024 > m=k*k > g=k*m > g > eeooff 1073741824 b) using the "inline" verion with three less-than symbols: $ less-than less-than less-than "k=1024; m=k*k; g=k*m; g" bc 1073741824 One nice advantage of using the triple less-than version is that the command can easily be recalled from command line history and re-executed. PS: in this "description", I had to use the name "less-than" to represent the less-than symbol because the commandlinefu input text box seems to eat up the real less-than symbols. Odd.

Restore user,group and mod of an entire website
I often use it at my work, on an ovh server with root ssh access and often have to change mod after having finished an operation. This command, replace the user, group and mod by the one required by apache to work.

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"

Stripping ^M at end of each line for files

Display error pages in report format
This command will return a full list of Error 404 pages in the given access log. The following variables have been given to awk Hostname ($2), ERROR Code ($9), Missing Item ($7), Referrer ($11) You can then send this into a file (>> /path/to/file), which you can open with OpenOffice as a CSV

Webcam view with vlc
Quick command to test your webcam. Press 'f' to toggle fullscreen. Can also use 'vlc v4l2://' if you want gui controls. For higher/smoother framerate lower the default resolution: $ cvlc v4l2:// :v4l2-width=320 :v4l2-height=240 &


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