SSH_ASKPASS

The ssh-add utility (see SSH agent for details) accepts a program in the environment variable SSH_ASKPASS that retrieves a passphrase from the user. This is especially useful to use the SSH agent from a script or a GUI (i.e. without a console).

Server Configuration

The following list will provide some hints how to configure you SSH daemon although most options will not have to be modified as they also contain reasonable defaults.

Perl Prototype

The following code forms the typical header for my Perl scripts:

Escape Characters

It is possible to control the SSH client while being logged in to a server:

Cloning Perl Arrays

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SSH Agent

The SSH agent stores unencrypted private keys to help you log in to servers without supplying your private key’s passphrase during retries.

Regenerating a Public Key

To regenerate your public key from the private key:

Perl Variable Aliases

When a variable is passed by value, Perl does not create a copy of the contents to build @_ but, rather, creates an alias to the contents of the original variable. Therefore, a memory blow-up is caused by reading from @_.

Cross Compiling Hint for Linux From Scratch has a new Maintainer

The crosscompiling hint is now maintained by Ted Bullock.

Quantiles

For a series of measurements $x_i = x_1, \dots, x_n$, it is useful to examine the magnitude of a certain fraction of the number of values.