The meaning of shell variable $#,$@,$0,$1,$2 in Linux

#!/bin/bash

#Created by Ley on 2014-11-14

#Testing the Paramters

echo "The Compleate list is%s\n" "$$"

echo "The Compleate list is%s\n" "$!"

echo "The Compleate list is%s\n" "$?"

echo "The Compleate list is%s\n" "$*"

echo "The Compleate list is%s\n" "[Email protected]"

echo "The Compleate list is%s\n" "$#"

echo "The Compleate list is%s\n" "$ $"

echo "The Compleate list is%s\n" "$"

echo "The Compleate list is%s\n" "$ $"

the meaning of shell variable $#,[email protected],$0,$1,$2 in Linux is explained:
Variable Description:
$$ 
the PID of the shell itself (ProcessID)
$! 
PID of the Shell's last running background process
$? 
end code of the last Run command (return value)
$- 
flag at a glance using the SET command
$* 
all parameter lists. such as "$*" in the Case of "" ", in the form of" $ $ ... $n "output all parameters.
[email protected]
all parameter lists. such as "[email protected]" with "" "in the case, with" $ "" $ "... All parameters are output in the form "$n".
$# 
number of arguments added to the shell
$
the name of the shell itself
$1~ $n
each parameter value added to the shell. $ $ is the 1th parameter, and the $ = is the 2nd parameter ....

[[email protected] ~]#./params.sh 123456 QQ

The Compleate list is%s\n 3406

The Compleate list is%s\n

The compleate list is%s\n 0

The Compleate list is%s\n 123456 QQ

The Compleate list is%s\n 123456 QQ

The Compleate list is%s\n 2

The Compleate list is%s\n./params.sh

The Compleate list is%s\n 123456

The Compleate list is%s\n QQ

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Linux shell variable $#,[email protected], meaning of $0,$1,$2