Experimenting with BASH

Since so much of hacking is rooted in exploitation and experimentation, the ability to quickly try different things is vital. The BASH shell and Perl are common on most machines and are all that is needed to experiment with exploitation.

Perl is an interpreted programming language with a print command that happens to be particularly suited to generating long sequences of characters. Perl can be used to execute instructions on the command line by using the -e switch like this:

reader@hacking:~/booksrc $ perl -e 'print "A" x 20;'
AAAAAAAAAAAAAAAAAAAA

This command tells Perl to execute the commands found between the single quotes—in this case, a single command of print "A" x 20;. This command prints the character A 20 times. ...

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