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unsetenv

Remove environment variable

Since R2022b

    Description

    unsetenv(varname) removes the operating system environment variable varname. If any elements in varname do not exist, then unsetenv has no effect.

    example

    Examples

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    Create environment variable myVar, and then check that it exists.

    setenv("myVar","myValue");
    isenv("myVar")
    ans = logical
       1
    
    

    Remove myVar, and then check that it no longer exists.

    unsetenv("myVar");
    isenv("myVar")
    ans = logical
       0
    
    

    Create multiple environment variables, and then check that they exist.

    setenv(["Var1" "Var2" "Var3" "Var4"],["Val1" "Val2" "Val3" "Val4"]);
    isenv(["Var1" "Var2"; "Var3" "Var4"])
    ans = 2×2 logical array
    
       1   1
       1   1
    
    

    Remove two of the environment variables using unsetenv, and then check that they no longer exist.

    unsetenv(["Var1" "Var4"]);
    isenv(["Var1" "Var2"; "Var3" "Var4"])
    ans = 2×2 logical array
    
       0   1
       1   0
    
    

    You can also remove environment variables using setenv with missing. Change the value of one environment variable and remove another.

    setenv(["Var2" "Var3"],["ValB" missing]);
    isenv(["Var1" "Var2"; "Var3" "Var4"])
    ans = 2×2 logical array
    
       0   1
       0   0
    
    

    Input Arguments

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    Environment variable names, specified as a string scalar, character vector, string array, or cell array of character vectors.

    Example: "PATH"

    Extended Capabilities

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    Version History

    Introduced in R2022b

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    See Also

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