![]() ![]() You can see this happening by playing with echoargs.exe (which uses the MS C/C++ runtime parser) inside the Command Prompt (not the PowerShell prompt). Because the inner quotes were not escaped using the Windows Command Processor parser escape character (the backslash), the command processor parser interpreted them as if the quoted parts contained “-script=” and “", therefore the space between scripts and temp isn’t actually within any quotes and hence split. Most (but annoyingly, not all) use the MS C/C++ runtime parser, and from what I can gather, it splits up the string into arguments by splitting at each space, unless the space is inside quotes. MS C/C++ runtime), has a separate set of rules for escaping things, therefore it is necessary to escape again to prevent it from interpreting the quotes. The Windows Command Processor program, depending on the parser used (e.g. When you execute an external command, Powershell grabs the command and the arguments (after the strings have been processed by Powershell and the Powershell escape characters removed), then passes it as a single string to the Windows Command Processor (or possibly straight to the Windows Shell/ Win32 API) program for execution. &$exe -p "-script=\ `" H:\backup\scripts temp\vss.cmd\ `" " E: M: P: %USERPROFILE% (I have no idea what expands them is cmd.exe still involved somehow?).įor example, the following command (which will work only in cmd.exe and not PowerShell in its current form), $dir will be passed to the external command as $dir), but it also means you can reference environment variables using the cmd.exe syntax, e.g. This means that you can’t reference any PowerShell variables after that operator (any references will be past literally, i.e. MS C/C++ runtime) and all those rules apply instead. Everything from that operator onwards is parsed by the Windows Command Processor (cmd.exe) parser used by the program (e.g. ![]() Instead of having to stuff around with escaping and quoting parameters to dodge the PowerShell parser, you can now use the -% operator which tells PowerShell to stop parsing from that point onward until the end of the line. If you’re using PowerShell v3 (which shipped with Windows 8 and Windows Server 2012 and is also available for Windows 7 / 2008 as a separate download), there is a new language feature that simplifies a lot of this. Notice that each parameter is considered a different argument, as opposed to a single string for all parameters. That is what the command line application expects. ![]()
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