NAME
        SystemTagList -- Have a shell execute a command line (V36)

   SYNOPSIS
        error = SystemTagList(command, tags)
        D0                      D1      D2

        long systemtaglist(strptr, struct tagitem *)

        error = System(command, tags)
        D0               D1      D2

        long system(strptr, struct tagitem *)

        error = SystemTags(command, Tag1, ...)

        long systemtags(strptr, ulong, ...)

   FUNCTION
        Similar to execute(), but does not read commands from the input
        filehandle.  Spawns a Shell process to execute the command, and
        returns the returncode the command produced, or -1 if the command
        could not be run for any reason.  The input and output filehandles
        will not be closed by System, you must close them (if needed) after
        System returns, if you specified them via SYS_Input or SYS_Output.

        By default the new process will use your current input() and output()
        filehandles.  Normal Shell command-line parsing will be done
        including redirection on 'command'.  The current directory and path
        will be inherited from your process.  Your path will be used to find
        the command (if no path is specified).

        Note that you may NOT pass the same filehandle for both SYS_Input
        and SYS_Output.  If you want input and output to both be to the same
        CON: window, pass a SYS_Input of a filehandle on the CON: window,
        and pass a SYS_Output of NULL.  The shell will automatically set
        the default output() stream to the window you passed via sys_input,
        by opening "*" on that handler.

        If used with the SYS_Asynch flag, it WILL close both it's input and
        output filehandles after running the command (even if these were
        your input() and output()!)

        Normally uses the boot (ROM) shell, but other shells can be specified
        via SYS_UserShell and SYS_CustomShell.  Normally, you should send
        things written by the user to the UserShell.  The UserShell defaults
        to the same shell as the boot shell.

        The tags are passed through to createnewproc() (tags that conflict
        with SystemTagList() will be filtered out).  This allows setting
        things like priority, etc for the new process.  The tags that are
        currently filtered out are:

                NP_Seglist
                NP_FreeSeglist
                NP_Entry
                NP_Input
                NP_Output
                NP_CloseInput
                NP_CloseOutput
                NP_HomeDir
                NP_Cli

   INPUTS
        command - Program and arguments
        tags    - see <dos/dostags.h>.  note that both systemtaglist()-
                  specific tags and tags from createnewproc() may be passed.

   RESULT
        error   - 0 for success, result from command, or -1.  Note that on
                  error, the caller is responsible for any filehandles or other
                  things passed in via tags.  -1 will only be returned if
                  dos could not create the new shell.  If the command is not
                  found the shell will return an error value, normally
                  RETURN_ERROR.

   SEE ALSO
        execute(), createnewproc(), <dos/dostags.h>, input(), output()