# Define executable

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**a <ashell executable name>**

The **-a** switch allows you to define an alternate executable name (besides ashell) for launching the instances of A-Shell. This is only useful when for some strange reason you have one or more custom versions of A-Shell with custom names. Note that although it is technically possible to plug any executable file name in with this option, PolyShell will not work correctly except with A-Shell.