DCL does not want the channel to be in raw mode.
 */
sys(cmd)
register char   *cmd;
{
        struct  dsc$descriptor  cdsc;
        struct  dsc$descriptor  *cdscp;
        long    status;
        long    substatus;
        long    iosb[2];

        status = SYS$QIOW(EFN, iochan, IO$_SETMODE, iosb, 0, 0,
                          oldmode, sizeof(oldmode), 0, 0, 0, 0);
        if (status!=SS$_NORMAL || (iosb[0]&0xFFFF)!=SS$_NORMAL)
                return (FALSE);
        cdscp = NULL;                           /* Assume DCL.          */
        if (cmd != NULL) {                      /* Build descriptor.    */
                cdsc.dsc$a_pointer = cmd;
                cdsc.dsc$w_length  = strlen(cmd);
                cdsc.dsc$b_dtype   = DSC$K_DTYPE_T;
                cdsc.dsc$b_class   = DSC$K_CLASS_S;
                cdscp = &cdsc;
        }
        status = LIB$SPAWN(cdscp, 0, 0, 0, 0, 0, &substatus, 0, 0, 0);
        if (status != SS$_NORMAL)
                substatus = status;
        status = SYS$QIOW(EFN, iochan, IO$_SETMODE, iosb, 0, 0,
                          newmode, sizeof(newmode), 0, 0, 0, 0);
        if (status!=SS$_NORMAL || (iosb[0]&0xFFFF)!=SS$_NORMAL)
                return (FALSE);
        if ((substatus&STS$M_SUCCESS) == 0)     /* Command failed.      */
                return (FALSE);
        return (TRUE);
}
#endif

#if	~AZTEC & MSDOS

/*
 * This routine, once again by Bob McNamara, is a C translation of the "system"
 * routine in the MWC-86 run time library. It differs from the "system" routine
 * in that it does not unconditionally append the string ".exe" to the end of
 * the command name. We needed to do this because we want to be able to spawn
 * off "command.com". We really do not understand what it does, but if you don't
 * do it exactly "malloc" starts doing very very strange things.
 */
sys(cmd, tail)
char    *cmd;
char    *tail;
{
#if MWC_86
        register unsigned n;
        extern   char     *__end;

        n = __end + 15;
        n >>= 4;
        n = ((n + dsreg() + 16) & 0xFFF0) + 16;
        return(execall(cmd, tail, n));
#endif

#if LATTICE
        return forklp(cmd, tail, NULL);
#endif
}
#endif
  long    iosb[2];

        status = SYS$QIOW(EFN, iochan, IO$_SETMODE, iosb, 0, 0,
                          oldmode, sizeof(oldmode), 0, 0, 0, 0);
        if (status!=SS$_NORMAL || (iosb[0]&0xFFFF)!=SS$_NORMAL)
                return (FALSE);
        cdscp = NULL;      (*term.t_flush)();
        ttclose();                              /* stty to old settings */
        if ((cp = getenv("SHELL")) != NULL && *cp != '\0')
                system(cp);
        else
#if	BSD
                system("exec /bin/csh");
#else
                system("exec /bin/sh");
#endif
        sgarbf = TRUE;
        sleep(2);
        ttopen();
        return(TRUE);
#endif
}

#if	V7 & BSD

bktoshell()		/* suspend MicroEMACS and wait to wake up */
{
	int pid;

	vttidy();
	pid = getpid();
	kill(pid,SIGTSTP);
}

rtfrmshell()
{
	ttopen();
	curwp->w_flag = WFHARD;
	refresh();
}
#endif

/*
 * Run a one-liner in a subjob. When the command returns, wait for a single
 * character to be typed, then mark the screen as garbage so a full repaint is
 * done. Bound to "C-X !".
 */
spawn(f, n)
{
        register int    s;
        char            line[NLINE];
#if     AMIGA
        long newcli;

        newcli = Open("CON:1/1/639/199/MicroEmacs Subprocess", NEW);
        if ((s=mlreply("CLI command: ", line, NLINE)) != TRUE)
                return (s);
        Execute(line,0,newcli);
        Close(newcli);
        (*term.t_getchar)();     /* Pause.               */
        sgarbf = TRUE;
        return(TRUE);
#endif
#if     VMS
        if ((s=mlreply("DCL command: ", line, NLINE)) != TRUE)
                return (s);
        (*term.t_putchar)('\n');                /* Already have '\r'    */
        (*term.t_flush)();
        s = sys(line);                          /* Run the command.     */
        mlputs("\r\n\n[End]");                  /* Pause.               */
        (*term.t_flush)();
        (*term.t_getchar)();
        sgarbf = TRUE;
        return (s);
#endif
#if     CPM
        mlwrite("Not in CP/M-86");
        return (FALSE);
#endif
#if     MSDOS
        if ((s=mlreply("MS-DOS command: ", line, NLINE)) != TRUE)
                return (s);
        system(line);
        mlputs("\r\n\n[End]");                  /* Pause.               */
        (*term.t_getchar)();     /* Pause.               */
        sgarbf = TRUE;
        return (TRUE);
#endif
#if     V7
        if ((s=mlreply("! ", line, NLINE)) != TRUE)
                return (s);
        (*term.t_putchar)('\n');                /* Already have '\r'    */
        (*term.t_flush)();
        ttclose();                              /* stty to old modes    */
        system(line);
        sleep(2);
        ttopen();
        mlputs("[End]");                        /* Pause.               */
        (*term.t_flush)();
        while ((s = (*term.t_getchar)()) != '\r' && s != ' ')
                ;
        sgarbf = TRUE;
        return (TRUE);
#endif
}

#if     VMS
/*
 * Run a command. The "cmd" is a pointer to a command string, or NULL if you
 * want to run a copy of DCL in the subjob (this is how the standard routine
 * LIB$SPAWN works. You have to do wierd stuff with the terminal on the way in
 * and the way out, because DCL does not want the channel to be in raw mode.
 */
sys(cmd)
register char   *cmd;
{
        struct  dsc$descriptor  cdsc;
        struct  dsc$descriptor  *cdscp;
        long    status;
        long    substatus;
        long    iosb[2];

        status = SYS$QIOW(EFN, iochan, IO$_SETMODE, iosb, 0, 0,
                          oldmode, sizeof(oldmode), 0, 0, 0, 0);
        if (status!=SS$_NORMAL || (iosb[0]&0xFFFF)!=SS$_NORMAL)
                return (FALSE);
        cdscp = NULL;                           /* Assume DCL.          */
        if (cmd != NULL) {                      /* Build descriptor.    */
                cdsc.dsc$a_pointer = cmd;
                cdsc.dsc$w_length  = strlen(cmd);
                cdsc.dsc$b_dtype   = DSC$K_DTYPE_T;
                cdsc.dsc$b_class   = DSC$K_CLASS_S;
                cdscp = &cdsc;
        }
        status = LIB$SPAWN(cdscp, 0, 0, 0, 0, 0, &substatus, 0, 0, 0);
        if (status != SS$_NORMAL)
                substatus = status;
        status = SYS$QIOW(EFN, iochan, IO$_SETMODE, iosb, 0, 0,
                          newmode, sizeof(newmode), 0, 0, 0, 0);
        if (status!=SS$_NORMAL || (iosb[0]&0xFFFF)!=SS$_NORMAL)
                return (FALSE);
        if ((substatus&STS$M_SUCCESS) == 0)     /* Command failed.      */
                return (FALSE);
        return (TRUE);
}
#endif

#if	~AZTEC & MSDOS

/*
 * This routine, once again by Bob McNamara, is a C translation of the "system"
 * routine in the MWC-86 run time library. It differs from the "system" routine
 * in that it does not unconditionally append the string ".exe" to the end of
 * the command name. We needed to do this because we want to be able to spawn
 * off "command.com". We really do not understand what it does, but if you don't
 * do it exactly "malloc" starts doing very very strange things.
 */
sys(cmd, tail)
char    *cmd;
char    *tail;
{
#if MWC_86
        register unsigned n;
        extern   char     *__end;

        n = __end + 15;
        n >>= 4;
        n = ((n + dsreg() + 16) & 0xFFF0) + 16;
        return(execall(cmd, tail, n));
#endif

#if LATTICE
        return forklp(cmd, tail, NULL);
#endif
}
#endif