Function SetWorkingDir

source/script2.cpp:7628–7667

ResultType SetWorkingDir(LPTSTR aNewDir)
// Throws a script runtime exception on failure, but only if the script has begun runtime execution.
// This function was added in v1.0.45.01 for the reason described below.
{
	// v1.0.45.01: Since A_ScriptDir omits the trailing backslash for roots of drives (such as C:),
	// and since that variable probably shouldn't be changed for backward compatibility, provide
	// the missing backslash to allow SetWorkingDir %A_ScriptDir% (and others) to work as expected
	// in the root of a drive.
	// Update in 2018: The reason it wouldn't by default is that "C:" is actually a reference to the
	// the current directory if it's on C: drive, otherwise a reference to the path contained by the
	// env var "=C:".  Similarly, "C:x" is a reference to "x" inside that directory.
	// For details, see https://blogs.msdn.microsoft.com/oldnewthing/20100506-00/?p=14133
	// Although the override here creates inconsistency between SetWorkingDir and everything else
	// that can accept "C:", it is most likely what the user wants, and now there's also backward-
	// compatibility to consider since this workaround has been in place since 2006.
	// v1.1.31.00: Add the slash up-front instead of attempting SetCurrentDirectory(_T("C:"))
	// and comparing the result, since the comparison would always yield "not equal" due to either
	// a trailing slash or the directory being incorrect.
	TCHAR drive_buf[4];
	if (aNewDir[0] && aNewDir[1] == ':' && !aNewDir[2])
	{
		drive_buf[0] = aNewDir[0];
		drive_buf[1] = aNewDir[1];
		drive_buf[2] = '\\';
		drive_buf[3] = '\0';
		aNewDir = drive_buf;
	}

	if (!SetCurrentDirectory(aNewDir)) // Caused by nonexistent directory, permission denied, etc.
		return FAIL;
	// Otherwise, the change to the working directory succeeded.

	// Other than during program startup, this should be the only place where the official
	// working dir can change.  The exception is FileSelect(), which changes the working
	// dir as the user navigates from folder to folder.  However, the whole purpose of
	// maintaining g_WorkingDir is to workaround that very issue.
	if (g_script.mIsReadyToExecute) // Callers want this done only during script runtime.
		UpdateWorkingDir(aNewDir);
	return OK;
}