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Windows environment variable: PATHEXT

The environment variable %PATHEXT% contains a list of file extensions (with the corresponding dot) that are separated by a semicolon (as are the paths in %PATH%).

The extensions usually specify a file type that can somehow be executed. Commonly seen extensions include:

.COM
.EXE
.BAT
.CMD
.VBS
.VBE
.JS
.JSE
.WSF
.WSH
.MSC

PATHEXT is used to start a program, batch file or script without explicitly specifying its suffix in cmd.exe or its start command.

There seems to be no Unix equivalent: http://unix.stackexchange.com/questions/280528.

PowerShell

In PowerShell, the extension of a (non-PowerShell script such as a Perl or Python script) must be listed in PATHEXT in order for the script to be executed in the current console (rather than spawning a new console in which the script is executed).

This behavior does not seem to be documented and might even be a bug, see also

bug report 9430 (With $env:PATHEXT including "." (extension-less files), PowerShell executes even associated console applications in a NEW console window), and
issue 15854 (Extensions of non-PowerShell scripts … must be listed in PATHEXT in order for the script to be run in the same console).
2021-11-15: This bug report apparently resulted in PowerShell Docs issue 8346: Add documentation on how PowerShell uses PATHEXT to run other interpreter scripts in the same console

Windows environment variable: PATHEXT

PowerShell

See also