Commands using perl (369)

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Testing reading speed with dd

Check your bash shell for vulnerability to the ShellShock exploit
If this command prints 'x' then your shell is vulnerable. Null output confirms that you are protected. Further reading: http://allanmcrae.com/2014/09/shellshock-and-arch-linux/

File rotation without rename command
Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.

Print IP of any interface. Useful for scripts.

Automatically rename tmux window using the current working directory
Adds a function that runs every time the prompt is rendered. The function grabs the CWD from PWD and issues a command to tmux to change the current window

uniq without pre-sorting
Reads stdin, and outputs each line only once - without sorting ahead of time. This does use more memory than your system's sort utility.

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.

convert flac to mp3
if you haven't already done so, install lame and flac: sudo apt-get install lame flac

Check if a process is running
Send signal 0 to the process. The return status ($?) can be used to determine if the process is running. 0 if it is, non-zero otherwise.

Execute a sudo command remotely, without displaying the password
The ssh command alone will execute the sudo command remotely, but the password will be visible in the terminal as you type it. The two stty commands disable the terminal from echoing the password back to you, which makes the remote sudo act as it does locally.


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