$ expands to the process ID of the shell. So, you can see the PID of the
current shell with echo $$.
> echo $$
36609
> zsh
> echo $$
45431
> exit
> echo $$
36609
See the Special Paramaters section of man bash for more details.
ACM@UIUC TIL
$ expands to the process ID of the shell. So, you can see the PID of the
current shell with echo $$.
> echo $$
36609
> zsh
> echo $$
45431
> exit
> echo $$
36609
See the Special Paramaters section of man bash for more details.