Re: [PATCH] ioctl_tty.2: Document ioctls: TCGETS2, TCSETS2, TCSETSW2, TCSETSF2

Re: [PATCH] ioctl_tty.2: Document ioctls: TCGETS2, TCSETS2, TCSETSW2, TCSETSF2

[Alejandro Colomar (man-pages) via Libc-alpha]

CC += glibc

On 7/30/21 2:09 AM, Pali Rohár wrote:
> Hello!
> 
> On Friday 30 July 2021 01:39:11 Alejandro Colomar (man-pages) wrote:
>> Hi Pali,
>>
>> On 7/29/21 7:31 PM, Pali Rohár wrote:
>>>
>>>>> +.IR "<asm/termbits.h>" .
>>
>> Is that the header that the user should include?
> 
> Yes.
> 
>> I don't know.  I typically avoid 'asm/' includes, but maybe in this case
>> it's the correct one.  Shouldn't the user maybe include <linux/termios.h>?
> 
> Problem is that you cannot include <linux/termios.h> together with
> <sys/ioctl.h>. It cause redefinition of symbols and compile errors.
> 
> And without <sys/ioctl.h> you cannot call ioctl() function which
> basically means that you cannot use TCGETS2 (as it is ioctl).

Seems fair.

> 
> Probably this is a bug in glibc header files...

I CCed glibc just in case they want to comment.

> 
> So currently it is needed to include <asm/termbits.h> file to use
> TCGETS2 ioctl. I'm not sure if it is "correct", but it is the only
> possible option for now about which I know (unless you want to
> copy+paste structures and macros from that file into your program, to
> avoid inclusion of asm/* files).

Re copy&paste: no thanks :)

> 
> If you want, I can send a patch for ioctl_tty.2 example section with
> simple C program to show how to use TCGETS2/TCSETS2 ioctl.

Great!  Please CC glibc in the patch.

> 
>> user@sqli:/usr/include$ grep -rn 'struct termios {'
>> asm-generic/termbits.h:12:struct termios {
>> user@sqli:/usr/include$ grep -rn '<asm-generic/termbits.h>'
>> x86_64-linux-gnu/asm/termbits.h:1:#include <asm-generic/termbits.h>
>> user@sqli:/usr/include$ grep -rn '<asm/termbits.h>'
>> asm-generic/termios.h:12:#include <asm/termbits.h>
>> user@sqli:/usr/include$ grep -rn '<asm-generic/termios.h>'
>> x86_64-linux-gnu/asm/termios.h:1:#include <asm-generic/termios.h>
>> user@sqli:/usr/include$ grep -rn '<asm/termios.h>'
>> linux/termios.h:6:#include <asm/termios.h>
>> user@sqli:/usr/include$ grep -rn '<linux/termios.h>'
>> user@sqli:/usr/include$
>>
>>
>>>>> +These ioctls are not supported on all architectures.
>>>>> +.IP
>>>>> +.BI "TCGETS2	struct termios2 *" argp
>>>>
>>>> Please follow the same style as in the rest of the page:
>>>>
>>>> .TP
>>>> .B TCGETS2
>>>> Argument:
>>>> .BI "struct termios2 *" argp
>>>>
>>>> Unless there's a good reason not to.
>>>
>>> Few lines below in this file is:
>>>
>>> .IR "struct termios\ *" .
>>> .IP
>>> .BI "TCGETA	struct termio *" argp
>>> .IP
>>> .BI "TCSETA	const struct termio *" argp
>>> .IP
>>> .BI "TCSETAW	const struct termio *" argp
>>> .IP
>>> .BI "TCSETAF	const struct termio *" argp
>>>
>>> Therefore I used same style for TCGETS2...
>>>
>>> So, how should I format this part to be consistent?
>>
>>
>> Hmm, sorry, I didn't see those.
> 
> Ah, now I see that Michael one hour later (after I sent this patch)
> fixed above style to another. See commit aceee9e827e6.
> 
> But changed it to another new style:
> 
> .RS
> .TS
> lb l.
> TCGETA	\fBstruct termio *\fPargp
> TCSETA	\fBconst struct termio *\fPargp
> TCSETAW	\fBconst struct termio *\fPargp
> TCSETAF	\fBconst struct termio *\fPargp
> .TE
> .RE
> 
>> So there's a mix in the file.
>> The more correct form is the one I used, so please use that one (the one
>> with .TP)
> 
> So, could you check with Michael which style to use? Because now there
> are 3 different (yours, Michael's and the one which was there before)
> and I'm really not sure what is correct...

Sorry, I was also confused, as I had Michael's version, and didn't see 
the table he reformatted, which I now understand was what you were doing 
(in the old format).  So if what you wrote corresponds to what Michael 
reformatted, please use Michael's new format (the table).

Thanks,

Alex

> 
>>
>> Thanks,
>>
>> Alex
>>
>>
>>>
>>>>> +.IP
>>>>> +.BI "TCSETS2	const struct termios2 *" argp
>>>>> +.IP
>>>>> +.BI "TCSETSW2	const struct termios2 *" argp
>>>>> +.IP
>>>>> +.BI "TCSETSF2	const struct termios2 *" argp
>>>>> +.PP
>>>>> +The following four ioctls are just like
>>>>> +.BR TCGETS ,
>>>>> +.BR TCSETS ,
>>>>> +.BR TCSETSW ,
>>>>> +.BR TCSETSF ,
>>>>> +except that they take a
>>>>>     .I "struct termio\ *"
>>>>>     instead of a
>>>>>     .IR "struct termios\ *" .
>>>>>
>>>>
>>>>
>>>> -- 
>>>> Alejandro Colomar
>>>> Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/
>>>> http://www.alejandro-colomar.es/
>>
>>
>> -- 
>> Alejandro Colomar
>> Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/
>> http://www.alejandro-colomar.es/


-- 
Alejandro Colomar
Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/
http://www.alejandro-colomar.es/

Re: [PATCH] ioctl_tty.2: Document ioctls: TCGETS2, TCSETS2, TCSETSW2, TCSETSF2

[Pali Rohár via Libc-alpha]

On Friday 30 July 2021 09:04:46 Alejandro Colomar (man-pages) wrote:
> CC += glibc
> 
> On 7/30/21 2:09 AM, Pali Rohár wrote:
> > Hello!
> > 
> > On Friday 30 July 2021 01:39:11 Alejandro Colomar (man-pages) wrote:
> > > Hi Pali,
> > > 
> > > On 7/29/21 7:31 PM, Pali Rohár wrote:
> > > > 
> > > > > > +.IR "<asm/termbits.h>" .
> > > 
> > > Is that the header that the user should include?
> > 
> > Yes.
> > 
> > > I don't know.  I typically avoid 'asm/' includes, but maybe in this case
> > > it's the correct one.  Shouldn't the user maybe include <linux/termios.h>?
> > 
> > Problem is that you cannot include <linux/termios.h> together with
> > <sys/ioctl.h>. It cause redefinition of symbols and compile errors.
> > 
> > And without <sys/ioctl.h> you cannot call ioctl() function which
> > basically means that you cannot use TCGETS2 (as it is ioctl).
> 
> Seems fair.
> 
> > 
> > Probably this is a bug in glibc header files...
> 
> I CCed glibc just in case they want to comment.
> 
> > 
> > So currently it is needed to include <asm/termbits.h> file to use
> > TCGETS2 ioctl. I'm not sure if it is "correct", but it is the only
> > possible option for now about which I know (unless you want to
> > copy+paste structures and macros from that file into your program, to
> > avoid inclusion of asm/* files).
> 
> Re copy&paste: no thanks :)
> 
> > 
> > If you want, I can send a patch for ioctl_tty.2 example section with
> > simple C program to show how to use TCGETS2/TCSETS2 ioctl.
> 
> Great!  Please CC glibc in the patch.
> 
> > 
> > > user@sqli:/usr/include$ grep -rn 'struct termios {'
> > > asm-generic/termbits.h:12:struct termios {
> > > user@sqli:/usr/include$ grep -rn '<asm-generic/termbits.h>'
> > > x86_64-linux-gnu/asm/termbits.h:1:#include <asm-generic/termbits.h>
> > > user@sqli:/usr/include$ grep -rn '<asm/termbits.h>'
> > > asm-generic/termios.h:12:#include <asm/termbits.h>
> > > user@sqli:/usr/include$ grep -rn '<asm-generic/termios.h>'
> > > x86_64-linux-gnu/asm/termios.h:1:#include <asm-generic/termios.h>
> > > user@sqli:/usr/include$ grep -rn '<asm/termios.h>'
> > > linux/termios.h:6:#include <asm/termios.h>
> > > user@sqli:/usr/include$ grep -rn '<linux/termios.h>'
> > > user@sqli:/usr/include$
> > > 
> > > 
> > > > > > +These ioctls are not supported on all architectures.
> > > > > > +.IP
> > > > > > +.BI "TCGETS2	struct termios2 *" argp
> > > > > 
> > > > > Please follow the same style as in the rest of the page:
> > > > > 
> > > > > .TP
> > > > > .B TCGETS2
> > > > > Argument:
> > > > > .BI "struct termios2 *" argp
> > > > > 
> > > > > Unless there's a good reason not to.
> > > > 
> > > > Few lines below in this file is:
> > > > 
> > > > .IR "struct termios\ *" .
> > > > .IP
> > > > .BI "TCGETA	struct termio *" argp
> > > > .IP
> > > > .BI "TCSETA	const struct termio *" argp
> > > > .IP
> > > > .BI "TCSETAW	const struct termio *" argp
> > > > .IP
> > > > .BI "TCSETAF	const struct termio *" argp
> > > > 
> > > > Therefore I used same style for TCGETS2...
> > > > 
> > > > So, how should I format this part to be consistent?
> > > 
> > > 
> > > Hmm, sorry, I didn't see those.
> > 
> > Ah, now I see that Michael one hour later (after I sent this patch)
> > fixed above style to another. See commit aceee9e827e6.
> > 
> > But changed it to another new style:
> > 
> > .RS
> > .TS
> > lb l.
> > TCGETA	\fBstruct termio *\fPargp
> > TCSETA	\fBconst struct termio *\fPargp
> > TCSETAW	\fBconst struct termio *\fPargp
> > TCSETAF	\fBconst struct termio *\fPargp
> > .TE
> > .RE
> > 
> > > So there's a mix in the file.
> > > The more correct form is the one I used, so please use that one (the one
> > > with .TP)
> > 
> > So, could you check with Michael which style to use? Because now there
> > are 3 different (yours, Michael's and the one which was there before)
> > and I'm really not sure what is correct...
> 
> Sorry, I was also confused, as I had Michael's version, and didn't see the
> table he reformatted, which I now understand was what you were doing (in the
> old format).  So if what you wrote corresponds to what Michael reformatted,
> please use Michael's new format (the table).
> 
> Thanks,
> 
> Alex

Hello! Now I sent a new version and reformatted this part according to
Michael style.

> > 
> > > 
> > > Thanks,
> > > 
> > > Alex
> > > 
> > > 
> > > > 
> > > > > > +.IP
> > > > > > +.BI "TCSETS2	const struct termios2 *" argp
> > > > > > +.IP
> > > > > > +.BI "TCSETSW2	const struct termios2 *" argp
> > > > > > +.IP
> > > > > > +.BI "TCSETSF2	const struct termios2 *" argp
> > > > > > +.PP
> > > > > > +The following four ioctls are just like
> > > > > > +.BR TCGETS ,
> > > > > > +.BR TCSETS ,
> > > > > > +.BR TCSETSW ,
> > > > > > +.BR TCSETSF ,
> > > > > > +except that they take a
> > > > > >     .I "struct termio\ *"
> > > > > >     instead of a
> > > > > >     .IR "struct termios\ *" .
> > > > > > 
> > > > > 
> > > > > 
> > > > > -- 
> > > > > Alejandro Colomar
> > > > > Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/
> > > > > http://www.alejandro-colomar.es/
> > > 
> > > 
> > > -- 
> > > Alejandro Colomar
> > > Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/
> > > http://www.alejandro-colomar.es/
> 
> 
> -- 
> Alejandro Colomar
> Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/
> http://www.alejandro-colomar.es/

Re: [PATCH] ioctl_tty.2: Document ioctls: TCGETS2, TCSETS2, TCSETSW2, TCSETSF2

[Alejandro Colomar (man-pages) via Libc-alpha]

Hi Pali,

On 7/30/21 2:21 AM, Pali Rohár wrote:
> On Friday 30 July 2021 01:39:11 Alejandro Colomar (man-pages) wrote:
>> user@sqli:/usr/include$ grep -rn 'struct termios {'
>> asm-generic/termbits.h:12:struct termios {
> 
> You have there a mistake. It is 'struct termios2', not 'struct termios'.
> 
> And for 'struct termios' it is more complicated as there are two
> different 'struct termios'. One in file <bits/termios.h> (included from
> <termios.h>) and one in file <asm-generic/termbits.h> (included from
> <linux/termios.h>).
> 
> Function tcsetattr() uses 'struct termios' from <bits/termios.h> and
> ioctl TCSETS uses 'struct termios' from <asm-generic/termbits.h>.

Right.

Anyway, it is in the same header:

user@sqli:/usr/include$ grep -rn 'struct termios2' | grep -v define
asm-generic/termbits.h:21:struct termios2 {


Regards,

Alex

> 
>> user@sqli:/usr/include$ grep -rn '<asm-generic/termbits.h>'
>> x86_64-linux-gnu/asm/termbits.h:1:#include <asm-generic/termbits.h>
>> user@sqli:/usr/include$ grep -rn '<asm/termbits.h>'
>> asm-generic/termios.h:12:#include <asm/termbits.h>
>> user@sqli:/usr/include$ grep -rn '<asm-generic/termios.h>'
>> x86_64-linux-gnu/asm/termios.h:1:#include <asm-generic/termios.h>
>> user@sqli:/usr/include$ grep -rn '<asm/termios.h>'
>> linux/termios.h:6:#include <asm/termios.h>
>> user@sqli:/usr/include$ grep -rn '<linux/termios.h>'
>> user@sqli:/usr/include$


-- 
Alejandro Colomar
Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/
http://www.alejandro-colomar.es/

[PATCH v2] ioctl_tty.2: Document ioctls: TCGETS2, TCSETS2, TCSETSW2, TCSETSF2

[Pali Rohár via Libc-alpha]

Signed-off-by: Pali Rohár <pali@kernel.org>

---
Changes in v2:
* Remove information about asm/termbits.h (will be in followup patch)
* Style fixes
---
 man2/ioctl_tty.2 | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/man2/ioctl_tty.2 b/man2/ioctl_tty.2
index 2a0effdae8ab..c1875530f0b1 100644
--- a/man2/ioctl_tty.2
+++ b/man2/ioctl_tty.2
@@ -77,6 +77,35 @@ The following four ioctls are just like
 .BR TCSETSW ,
 .BR TCSETSF ,
 except that they take a
+.I "struct termios2\ *"
+instead of a
+.IR "struct termios\ *" .
+If struct member
+.B c_cflag
+contains
+.B BOTHER
+then baudrate is stored in struct members
+.B c_ispeed
+and
+.B c_ospeed
+as integer values.
+These ioctls are not supported on all architectures.
+.RS
+.TS
+lb l.
+TCGETS2	\fBstruct termios2 *\fPargp
+TCSETS2	\fBconst struct termios2 *\fPargp
+TCSETSW2	\fBconst struct termios2 *\fPargp
+TCSETSF2	\fBconst struct termios2 *\fPargp
+.TE
+.RE
+.PP
+The following four ioctls are just like
+.BR TCGETS ,
+.BR TCSETS ,
+.BR TCSETSW ,
+.BR TCSETSF ,
+except that they take a
 .I "struct termio\ *"
 instead of a
 .IR "struct termios\ *" .
-- 
2.20.1

Re: [PATCH v2] ioctl_tty.2: Document ioctls: TCGETS2, TCSETS2, TCSETSW2, TCSETSF2

[Alejandro Colomar (man-pages) via Libc-alpha]

Hi Pali,

On 7/30/21 12:48 PM, Pali Rohár wrote:
> Signed-off-by: Pali Rohár <pali@kernel.org>
> 

Patch applied.  Thanks,

Alex

> ---
> Changes in v2:
> * Remove information about asm/termbits.h (will be in followup patch)
> * Style fixes
> ---
>   man2/ioctl_tty.2 | 29 +++++++++++++++++++++++++++++
>   1 file changed, 29 insertions(+)
> 
> diff --git a/man2/ioctl_tty.2 b/man2/ioctl_tty.2
> index 2a0effdae8ab..c1875530f0b1 100644
> --- a/man2/ioctl_tty.2
> +++ b/man2/ioctl_tty.2
> @@ -77,6 +77,35 @@ The following four ioctls are just like
>   .BR TCSETSW ,
>   .BR TCSETSF ,
>   except that they take a
> +.I "struct termios2\ *"
> +instead of a
> +.IR "struct termios\ *" .
> +If struct member
> +.B c_cflag
> +contains
> +.B BOTHER
> +then baudrate is stored in struct members
> +.B c_ispeed
> +and
> +.B c_ospeed
> +as integer values.
> +These ioctls are not supported on all architectures.
> +.RS
> +.TS
> +lb l.
> +TCGETS2	\fBstruct termios2 *\fPargp
> +TCSETS2	\fBconst struct termios2 *\fPargp
> +TCSETSW2	\fBconst struct termios2 *\fPargp
> +TCSETSF2	\fBconst struct termios2 *\fPargp
> +.TE
> +.RE
> +.PP
> +The following four ioctls are just like
> +.BR TCGETS ,
> +.BR TCSETS ,
> +.BR TCSETSW ,
> +.BR TCSETSF ,
> +except that they take a
>   .I "struct termio\ *"
>   instead of a
>   .IR "struct termios\ *" .
> 


-- 
Alejandro Colomar
Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/
http://www.alejandro-colomar.es/