Commands by pyrho (5)

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Using a single sudo to run multiple && arguments
Bash's here string

View non-printing characters with cat
Useful to detect number of tabs in an empty line, DOS newline (carriage return + newline). A tool that can help you understand why your parsing is not working.

change ownership en masse of files owned by a specific user, including files and directories with spaces
In the example, uid 0 is root. foo:foo are the user:group you want to make owner and group. '.' is the "current directory and below." -print0 and -0 indicate that filenames and directories "are terminated by a null character instead of by whitespace."

Show all listening and established ports TCP and UDP together with the PID of the associated process
Easy to remenber. Fot TCP only use: netstat -plant

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

autossh + ssh + screen = super rad perma-sessions
Only useful for really flakey connections (but im stuck with one for now). Though if youre in this situation ive found this to be a good way to run autossh and it does a pretty good job of detecting when the session is down and restarting. Combined with the -t and screen commands this pops you back into your working session lickety split w/ as few headaches as possible. And if autossh is a bit slow at detecting the downed ssh connection, just run this in another tab/terminal window to notify autossh that it should drop it and start over. Basically for when polling is too slow. kill -SIGUSR1 `pgrep autossh`

Install pip with Proxy
Installs pip packages defining a proxy

Create a 5 MB blank file via a seek hole
Similar to the original, but is much faster since it only needs to write the last byte as zero. A diff on testfile and testfile.seek will return that they are the same.

Create the authorization header required for a Twitter stream feed
This is the FOURTH in a set of five commands. Please see my other commands for the previous three steps. This command builds the authorization header required by Twitter. For this command to work, see my previous 3 commands (step1, step2 and step3) as they are required to build the environment variables used in this command. For more information on the authorization header, go to dev.twitter.com/apps, click on any of your apps (or create a new one) and then click on the "OAuth Tool" tab.

function to edit your history file
eh stands for Edit History . Frequently, I'll mistype a command, and then step back through my history and correct the command. As a result, both the correct and incorrect commands are in my history file. I wanted a simple way to remove the incorrect command so I don't run it by mistake. . When running this function, first the ~/bash_history file is updated, then you edit the file in vi, and then the saved history file is loaded back into memory for current usage. . while in vi, remember that `Shift-G` sends you to the bottom of the file, and `dd` removes a line. . this command is different than bash built-in `fc` because it does not run the command after editing.


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