C Shell運算符
本教程列出了所有C Shell的運算符。在這裏，大部分的運算符都是跟C語言編程很相似。
運算符優先級遞減的順序如下：
算術和邏輯運算符：
運算符
描述
( )
Change precedence
~
1's complement
!
Logical negation
*
Multiply
/
Divide
%
Modulo
+
Add
-
Subtract
<<
Left shift
>>
Right shift
==
String comparison for equality
!=
String comparison for non equality
=~
Pattern matching
&
Bitwise "and"
^
Bitwise "exclusive or"
|
Bitwise "inclusive or"
&&
Logical "and"
||
Logical "or"
++
Increment
--
Decrement
=
Assignment
*=
Multiply left side by right side and update left side
/=
Divide left side by right side and update left side
+=
Add left side to right side and update left side
-=
Subtract left side from right side and update left side
^=
"Exclusive or" left side to right side and update left side
%=
Divide left by right side and update left side with remainder
文件測試操作：
有以下操作測試與Unix文件相關聯的各種屬性。
操作符
描述
-r file
Checks if file is readable if yes then condition becomes true.
-w file
Check if file is writable if yes then condition becomes true.
-x file
Check if file is execute if yes then condition becomes true.
-f file
Check if file is an ordinary file as opposed to a directory or special file if yes then condition becomes true.
-z file
Check if file has size greater than 0 if yes then condition becomes true.
-d file
Check if file is a directory if yes then condition becomes true.
-e file
Check if file exists. Is true even if file is a directory but exists.
-o file
Check if user owns the file. It returns true if user is the owner of the file.