Commands by grokskookum (19)

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export iPad App list to txt file
This will generate the same output without changing the current directory, and filepath will be relative to the current directory. Note: it will (still) fail if your iTunes library is in a non-standard location.

Print text string vertically, one character per line.

Add temporary entry to authorized_keys
If you frequently need to connect to your ubersecure mainframe from various uberunsafe machines, you have to face difficult decision: (a) type the password everytime during the session (lame), (b) add local public key to mainframes authorized_keys file (unsafe), (c) as above, but remove this key at the end of the session (pain in the a55). So let's say you save The Command to tempauth file in bin directory of your mainframe's account and make it executable. Then, while you're on one of these unsafe ones, do: $ cat $HOME/.ssh/id_rsa.pub|ssh 5z474n@mainframe.nl bin/tempauth 30 and password prompts stop the harassment for 30 minutes and you don't have to care to remove the unsafe key after that.

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"

prints line numbers

C one-liners
$ /lib/ld-linux.so.2 is the runtime linker/loader for ELF binaries on Linux. =(cmd) is a zsh trick to take the output for the command "inside" it and save it to a temporary file. $ echo -e 'blah' | gcc -x c -o /dev/stdout - pipes the C source to gcc. -x c tells gcc that it's compiling C (which is required if it's reading from a pipe). -o /dev/stdout - tells it to write the binary to standard output and read the source from standard input. because of the the =() thing, the compiled output is stashed in a tempfile, which the loader then runs and executes, and the shell tosses the tempfile away immediately after running it.

Install pip with Proxy
Installs pip packages defining a proxy

Find 'foo' string inside files

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"

Add a line to a file using sudo
This is the solution to the common mistake made by sudo newbies, since $ sudo echo "foo bar" >> /path/to/some/file does NOT add to the file as root. Alternatively, $ sudo echo "foo bar" > /path/to/some/file should be replaced by $ echo "foo bar" | sudo tee /path/to/some/file And you can add a >/dev/null in the end if you're not interested in the tee stdout : $ echo "foo bar" | sudo tee -a /path/to/some/file >/dev/null


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