[RESEND][PATCH] sendfile.2: Fix description of the out_fd

[RESEND][PATCH] sendfile.2: Fix description of the out_fd

[Akira Fujita]

commit cc56f7de7f00d188c7c4da1e9861581853b9e92f made
sendfile(2) can work with any output file.
Therefore the out_fd of sendfile(2) can refer to any file,
but current manual (man-pages-3.32) has not been changed so far.

Signed-off-by: Akira Fujita <a-fujita-cUW4a6blu5N8UrSeD/g0lQ@public.gmane.org>
---
 sendfile.2 |   16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)
--- man-pages-3.32-a/man2/sendfile.2	2010-12-03 16:01:59.000000000 +0900
+++ man-pages-3.32-b/man2/sendfile.2	2011-03-09 10:34:53.000000000 +0900
@@ -87,15 +87,17 @@ and the file offset will be updated by t
 .I count
 is the number of bytes to copy between the file descriptors.

-Presently (Linux 2.6.9):
-.IR in_fd ,
+.IR in_fd
 must correspond to a file which supports
 .BR mmap (2)-like
 operations
-(i.e., it cannot be a socket);
-and
-.I out_fd
-must refer to a socket.
+(i.e., it cannot be a socket).
+
+.IR out_fd
+was required to be a socket, but since Linux 2.6.33 it can be
+any file. If it is a regular file, then
+.BR sendfile()
+changes its offset appropriately.

 Applications may wish to fall back to
 .BR read (2)/ write (2)
@@ -165,7 +167,7 @@ to minimize the number of packets and to

 In Linux 2.4 and earlier,
 .I out_fd
-could refer to a regular file, and
+could also refer to a regular file, and
 .BR sendfile ()
 changed the current offset of that file.
--
To unsubscribe from this list: send the line "unsubscribe linux-man" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [RESEND][PATCH] sendfile.2: Fix description of the out_fd

[Michael Kerrisk]

Hello Akira,

2011/3/9 Akira Fujita <a-fujita-cUW4a6blu5N8UrSeD/g0lQ@public.gmane.org>:
> commit cc56f7de7f00d188c7c4da1e9861581853b9e92f made
> sendfile(2) can work with any output file.
> Therefore the out_fd of sendfile(2) can refer to any file,
> but current manual (man-pages-3.32) has not been changed so far.

Thank you for this report! Some notes below.

> Signed-off-by: Akira Fujita <a-fujita-cUW4a6blu5N8UrSeD/g0lQ@public.gmane.org>
> ---
>  sendfile.2 |   16 +++++++++-------
>  1 file changed, 9 insertions(+), 7 deletions(-)
> --- man-pages-3.32-a/man2/sendfile.2    2010-12-03 16:01:59.000000000 +0900
> +++ man-pages-3.32-b/man2/sendfile.2    2011-03-09 10:34:53.000000000 +0900
> @@ -87,15 +87,17 @@ and the file offset will be updated by t
>  .I count
>  is the number of bytes to copy between the file descriptors.
>
> -Presently (Linux 2.6.9):
> -.IR in_fd ,
> +.IR in_fd
>  must correspond to a file which supports
>  .BR mmap (2)-like
>  operations
> -(i.e., it cannot be a socket);

You removed that piece, but I believe nothing changed for 'in_fd', so
I kept that piece.

> -and
> -.I out_fd
> -must refer to a socket.
> +(i.e., it cannot be a socket).
> +
> +.IR out_fd
> +was required to be a socket, but since Linux 2.6.33 it can be
> +any file. If it is a regular file, then
> +.BR sendfile()
> +changes its offset appropriately.
>
>  Applications may wish to fall back to
>  .BR read (2)/ write (2)
> @@ -165,7 +167,7 @@ to minimize the number of packets and to
>
>  In Linux 2.4 and earlier,
>  .I out_fd
> -could refer to a regular file, and
> +could also refer to a regular file, and
>  .BR sendfile ()
>  changed the current offset of that file.

For 3.33 I applied a slightly modified version of you patch; see below.

Cheers,

Michael

--- a/man2/sendfile.2
+++ b/man2/sendfile.2
@@ -92,10 +92,14 @@ The
 argument must correspond to a file which supports
 .BR mmap (2)-like
 operations
-(i.e., it cannot be a socket);
-and
+(i.e., it cannot be a socket).
+In Linux kernels before 2.6.33,
 .I out_fd
 must refer to a socket.
+Since Linux 2.6.33 it can be any file.
+If it is a regular file, then
+.BR sendfile()
+changes the file offset offset appropriately.

 Applications may wish to fall back to
 .BR read (2)/ write (2)
@@ -165,7 +169,7 @@ to minimize the number of packets and to tune performance.

 In Linux 2.4 and earlier,
 .I out_fd
-could refer to a regular file, and
+could also refer to a regular file, and
 .BR sendfile ()
 changed the current offset of that file.


-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Author of "The Linux Programming Interface"; http://man7.org/tlpi/
--
To unsubscribe from this list: send the line "unsubscribe linux-man" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [RESEND][PATCH] sendfile.2: Fix description of the out_fd

[Akira Fujita]

Hello Michael,

Thank you for your work!

Regards,
Akira Fujita

(2011/09/12 1:00), Michael Kerrisk wrote:
> Hello Akira,
> 
> 2011/3/9 Akira Fujita<a-fujita-cUW4a6blu5N8UrSeD/g0lQ@public.gmane.org>:
>> commit cc56f7de7f00d188c7c4da1e9861581853b9e92f made
>> sendfile(2) can work with any output file.
>> Therefore the out_fd of sendfile(2) can refer to any file,
>> but current manual (man-pages-3.32) has not been changed so far.
> 
> Thank you for this report! Some notes below.
> 
>> Signed-off-by: Akira Fujita<a-fujita-cUW4a6blu5N8UrSeD/g0lQ@public.gmane.org>
>> ---
>>   sendfile.2 |   16 +++++++++-------
>>   1 file changed, 9 insertions(+), 7 deletions(-)
>> --- man-pages-3.32-a/man2/sendfile.2    2010-12-03 16:01:59.000000000 +0900
>> +++ man-pages-3.32-b/man2/sendfile.2    2011-03-09 10:34:53.000000000 +0900
>> @@ -87,15 +87,17 @@ and the file offset will be updated by t
>>   .I count
>>   is the number of bytes to copy between the file descriptors.
>>
>> -Presently (Linux 2.6.9):
>> -.IR in_fd ,
>> +.IR in_fd
>>   must correspond to a file which supports
>>   .BR mmap (2)-like
>>   operations
>> -(i.e., it cannot be a socket);
> 
> You removed that piece, but I believe nothing changed for 'in_fd', so
> I kept that piece.
> 
>> -and
>> -.I out_fd
>> -must refer to a socket.
>> +(i.e., it cannot be a socket).
>> +
>> +.IR out_fd
>> +was required to be a socket, but since Linux 2.6.33 it can be
>> +any file. If it is a regular file, then
>> +.BR sendfile()
>> +changes its offset appropriately.
>>
>>   Applications may wish to fall back to
>>   .BR read (2)/ write (2)
>> @@ -165,7 +167,7 @@ to minimize the number of packets and to
>>
>>   In Linux 2.4 and earlier,
>>   .I out_fd
>> -could refer to a regular file, and
>> +could also refer to a regular file, and
>>   .BR sendfile ()
>>   changed the current offset of that file.
> 
> For 3.33 I applied a slightly modified version of you patch; see below.
> 
> Cheers,
> 
> Michael
> 
> --- a/man2/sendfile.2
> +++ b/man2/sendfile.2
> @@ -92,10 +92,14 @@ The
>   argument must correspond to a file which supports
>   .BR mmap (2)-like
>   operations
> -(i.e., it cannot be a socket);
> -and
> +(i.e., it cannot be a socket).
> +In Linux kernels before 2.6.33,
>   .I out_fd
>   must refer to a socket.
> +Since Linux 2.6.33 it can be any file.
> +If it is a regular file, then
> +.BR sendfile()
> +changes the file offset offset appropriately.
> 
>   Applications may wish to fall back to
>   .BR read (2)/ write (2)
> @@ -165,7 +169,7 @@ to minimize the number of packets and to tune performance.
> 
>   In Linux 2.4 and earlier,
>   .I out_fd
> -could refer to a regular file, and
> +could also refer to a regular file, and
>   .BR sendfile ()
>   changed the current offset of that file.
> 
> 
--
To unsubscribe from this list: send the line "unsubscribe linux-man" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [RESEND][PATCH] sendfile.2: Fix description of the out_fd

[Stefan Puiu]

HI,

On Sun, Sep 11, 2011 at 7:00 PM, Michael Kerrisk <mtk.manpages-Re5JQEeQqe8@public.gmane.orgm> wrote:
[...]
>
> For 3.33 I applied a slightly modified version of you patch; see below.
>
> Cheers,
>
> Michael
>
> --- a/man2/sendfile.2
> +++ b/man2/sendfile.2
> @@ -92,10 +92,14 @@ The
>  argument must correspond to a file which supports
>  .BR mmap (2)-like
>  operations
> -(i.e., it cannot be a socket);
> -and
> +(i.e., it cannot be a socket).
> +In Linux kernels before 2.6.33,
>  .I out_fd
>  must refer to a socket.
> +Since Linux 2.6.33 it can be any file.
> +If it is a regular file, then
> +.BR sendfile()
> +changes the file offset offset appropriately.

You wrote 'offset' twice here, I guess it's a typo, unless I'm missing
something...

Thanks,
Stefan.
--
To unsubscribe from this list: send the line "unsubscribe linux-man" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [RESEND][PATCH] sendfile.2: Fix description of the out_fd

[Michael Kerrisk]

On Fri, Sep 16, 2011 at 8:24 AM, Stefan Puiu <stefan.puiu-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> HI,
>
> On Sun, Sep 11, 2011 at 7:00 PM, Michael Kerrisk <mtk.manpages@gmail.com> wrote:
> [...]
>>
>> For 3.33 I applied a slightly modified version of you patch; see below.
>>
>> Cheers,
>>
>> Michael
>>
>> --- a/man2/sendfile.2
>> +++ b/man2/sendfile.2
>> @@ -92,10 +92,14 @@ The
>>  argument must correspond to a file which supports
>>  .BR mmap (2)-like
>>  operations
>> -(i.e., it cannot be a socket);
>> -and
>> +(i.e., it cannot be a socket).
>> +In Linux kernels before 2.6.33,
>>  .I out_fd
>>  must refer to a socket.
>> +Since Linux 2.6.33 it can be any file.
>> +If it is a regular file, then
>> +.BR sendfile()
>> +changes the file offset offset appropriately.
>
> You wrote 'offset' twice here, I guess it's a typo, unless I'm missing
> something...

Thanks Stefan. Fixed now.

Cheers,

Michael


-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Author of "The Linux Programming Interface"; http://man7.org/tlpi/
--
To unsubscribe from this list: send the line "unsubscribe linux-man" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html