bash - What are the special dollar sign shell variables? - Stack Overflow

Original source (stackoverflow.com)

Clipped on: 2013-10-02

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In Bash, there appear to be several variables which hold special, consistently-meaning values. For instance,

./myprogram &; echo $!

will return the PID of the process which backgrounded myprogram. I know of others, such as $? which I think is the current TTY. Are there others?

edited Jul 16 '12 at 22:04