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[[ ]]

[[ expression ]]

Korn shell only. Same as test expression or [ expression ] , except that [[ ]] allows additional operators. Word splitting and filename expansion are disabled. Note that the brackets ([ ] ) are typed literally, and that they must be surrounded by whitespace.

Additional Operators


Logical AND of test expressions (short circuit).


Logical OR of test expressions (short circuit).


First string is lexically "less than" the second.


First string is lexically "greater than" the second.

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