Re: [PATCH 1/1] document posix_openpt

[Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>]

On 12/04/23 09:45, Gavin Smith via Libc-alpha wrote:
> I copied the safety information from getpt, as I couldn't get this
> information in full from anywhere else.
> 
> Your patch submission guide is contradictory as to whether to
> use Signed-off-by or not
> (https://sourceware.org/glibc/wiki/Contribution%20checklist):
> 
>> ... you just add a line saying:
>>     Signed-off-by: ...
> 
>> The project does not support or use "Signed-off-by" lines
> 
> 
> commit be1468aa984d91e55db7719034ca9b8e53a7a136
> Author: Gavin Smith <gavinsmith0123@gmail.com>
> Date:   Wed Apr 12 13:36:47 2023 +0100
> 
>     manual: document posix_openpt (bug 17010)
>     
>     * manual/terminal.texi (Allocation):
>     Document posix_openpt.  State that getpt is similar to posix_openpt.
>     Use posix_openpt instead of getpt in example.
>     
>     Signed-off-by: Gavin Smith <gavinsmith0123@gmail.com>

LGTM, I am just no sure which standard to use.

> 
> diff --git a/manual/terminal.texi b/manual/terminal.texi
> index 7293bfb393..bdaee56053 100644
> --- a/manual/terminal.texi
> +++ b/manual/terminal.texi
> @@ -1947,6 +1947,33 @@ This subsection describes functions for allocating a pseudo-terminal,
>  and for making this pseudo-terminal available for actual use.  These
>  functions are declared in the header file @file{stdlib.h}.
>  
> +@deftypefun int posix_openpt (int @var{flags})
> +@standards{POSIX.1, stdlib.h}

Shouldn't it be POSIX.2, since it is define for _XOPEN_SOURCE >= 600?

> +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{@acsfd{}}}
> +
> +@code{posix_openpt} returns a new file descriptor for the next
> +available master pseudo-terminal.  In the case of an error, it returns
> +a value of @math{-1} instead, and sets @code{errno} to indicate
> +the error.  @xref{Opening and Closing Files} for possible values
> +of @code{errno}.
> +
> +@var{flags} is a bit mask created from a bitwise OR of zero or more
> +of the following flags:
> +
> +@table @code
> +@item O_RDWR
> +Open the device for both reading and writing.  It is usual to specify
> +this flag.
> +@item O_NOCTTY
> +Do not make the device the controlling terminal for the process.
> +@end table
> +
> +These flags are defined in @file{fcntl.h}.  @xref{Access Modes}.
> +
> +For this function to be available, @code{_XOPEN_SOURCE} must be defined
> +to a value greater than @samp{600}.  @xref{Feature Test Macros}.
> +@end deftypefun
> +
>  @deftypefun int getpt (void)
>  @standards{GNU, stdlib.h}
>  @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{@acsfd{}}}
> @@ -1957,6 +1984,10 @@ functions are declared in the header file @file{stdlib.h}.
>  @c a devfs, and returns the fd; static variables devpts_mounted and
>  @c have_no_dev_ptmx are safely initialized so as to avoid repeated
>  @c tests.
> +
> +@code{getpt} is similar to @code{posix_openpt}.  This function is a
> +GNU extension and should not be used in portable programs.
> +
>  The @code{getpt} function returns a new file descriptor for the next
>  available master pseudo-terminal.  The normal return value from
>  @code{getpt} is a non-negative integer file descriptor.  In the case of
> @@ -1967,8 +1998,6 @@ an error, a value of @math{-1} is returned instead.  The following
>  @item ENOENT
>  There are no free master pseudo-terminals available.
>  @end table
> -
> -This function is a GNU extension.
>  @end deftypefun
>  
>  @deftypefun int grantpt (int @var{filedes})
> @@ -2118,6 +2147,7 @@ This function is a GNU extension.
>  @end deftypefun
>  
>  Typical usage of these functions is illustrated by the following example:
> +
>  @smallexample
>  int
>  open_pty_pair (int *amaster, int *aslave)
> @@ -2125,7 +2155,7 @@ open_pty_pair (int *amaster, int *aslave)
>    int master, slave;
>    char *name;
>  
> -  master = getpt ();
> +  master = posix_openpt (O_RDWR | O_NOCTTY);
>    if (master < 0)
>      return 0;
>  
> 

Ok.