deprecated TIOCSPGRP and TIOCGPGRP ioctl command

[Garrett Cooper]

On Nov 9, 2011, at 4:49 PM, Peter Wemm wrote:

> On Wed, Nov 9, 2011 at 3:39 PM, Giovanni Trematerra <gianni at freebsd.org> wrote:
>> Are they deprecated enough to be removed, now?
>> FYI FIFO doesn't support them.
>> 
>> --
>> Gianni
>> 
>> =================================
>> --- sys/kern/sys_pipe.c (revision 227233)
>> +++ sys/kern/sys_pipe.c (working copy)
>> @@ -1304,17 +1304,6 @@ pipe_ioctl(fp, cmd, data, active_cred, td)
>>        *(int *)data = fgetown(&mpipe->pipe_sigio);
>>        break;
>> 
>> -   /* This is deprecated, FIOSETOWN should be used instead. */
>> -   case TIOCSPGRP:
>> -       PIPE_UNLOCK(mpipe);
>> -       error = fsetown(-(*(int *)data), &mpipe->pipe_sigio);
>> -       goto out_unlocked;
>> -
>> -   /* This is deprecated, FIOGETOWN should be used instead. */
>> -   case TIOCGPGRP:
>> -       *(int *)data = -fgetown(&mpipe->pipe_sigio);
>> -       break;
>> -
>>    default:
>>        error = ENOTTY;
> 
> Be very very careful with this.  It's part of the classic BSD job
> control API.  It would be wise to survey whether any ports shells use
> this.
> 
> You might also want to consider things like this in libc:
> int
> tcsetpgrp(int fd, pid_t pgrp)
> {
>        int s;
> 
>        s = pgrp;
>        return (_ioctl(fd, TIOCSPGRP, &s));
> }
> Our own libc code uses this, albeit on an API intended to be used on a tty.
> 
> The shell I'd be most concerned about is csh/tcsh in our tree. It has
> quite an #ifdef legacy layer and I couldn't convince myself it wasn't
> using this indirectly (or the tc* functions) on pipes.
> 
> It might also be an idea to see if the linux compat layer can be
> switched over to using the newer API.

Move to a compat library perhaps?
-Garrett