All the suggested updates have been made.

Made all the requested updates. Used terminology from https://standards.ieee.org/project/1003_1.html to justify writing .St -p1003.1 Base Specifications, Issue 8.

In D27787#621465, @kib wrote:

It is strange that the file is named tcsetwinsize.3 while the first function (correctly, by alphabetical order) is tcgetwinsize. I suggest to rename source to tcgetwinsize.3.

@kib All of your comments are very helpful. I am working on the improvements now.

Added the fact that SIGWINCH is only sent to those processes in the foreground process group that have the terminal as their controlling terminal.

In D27650#620599, @0.gangzta_gmail.com wrote:

OTOH, while it's not a big deal anymore, I wonder why some of the other platforms such as NetBSD have chosen to not put the winsize materials under _NETBSD_SOURCE.

@kib I will definitely keep my promise. May I please have until the end of the weekend to work on this? I might actually be done way before that, in which case I will submit it immediately after I am done.

Updated license.

In D27650#620577, @kib wrote:

Surprisingly, it looks fine.

Removed SCCS line.

I have made the requested changes. Notes:

The winsize related material should currently be under __BSD_VISIBLE guard.

Removes #include <sys/ttycom.h> from termios.h to prevent including unnecessary definitions in the posix header. Since struct winsize is still needed, it is now separately defined in sys/_termios.h with appropriate guards added.

@kib Beautiful! Thank you for the explanation :D I will do my homework right away.

To further strengthen my argument, I would like to point out that since our tcgetwinsize() and tcsetwinsize() are using ioctl()+TIOCGWINSZ/TIOCSWINSZ to implement tcgetwinsize()/tcsetwinsze(), our struct winsize must be the same as the one being used by sys/ioctl.h, which is included from sys/ttycom.h. Also, like NetBSD, musl libc does not directly define struct winsize in their termios.h either; see https://git.musl-libc.org/cgit/musl/tree/include/termios.h; they are defining it by including <bits/alltypes.h>. Sorry for playing devil's advocate, but I want to make sure that I learn things right: why should we place the tcgetwinsize(), tcsetwinsize() declarations under __POSIX_VISIBLE when they are not a part of POSIX *yet*?

Straightforward question: Why does struct winsize have to be defined explicitly in this file even though struct termios does not? The CURRENT POSIX specs demand that struct termios be defined in termios.h. Someone please answer this. If this is answered, then I will not hesitate to explicitly define struct winsize here anymore, even though redundant definitions in various files instead of a central location [ sys/ttycom.h ] seems like bad practice.

Another note: won't defining the same struct [ struct winsize ] in 2 different places [ sys/ttycom.h and termios.h ] just make it harder to maintain in case we need to modify the definition in the future? sys/ttycom.h already provides appropriate guards that will prevent multiple definition in case one's program includes both termios.h and sys/ioctl.h.

@yuripv I have added you to the reviewer list.

Sorry here is the exact link to the current termios.h POSIX specification: https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/termios.h.html. Please note the line "The <termios.h> header shall define the termios structure, which shall include at least the following members..."; then note that the FreeBSD termios.h does not directly define struct termios; instead, it imports the definition from #include <sys/_termios.h>.

@kib I moved the patches here from Bugzilla. I have also updated them. Can you please take another look at them?

Restored empty lines in tcgetattr() and introduced empty lines in tcgetwinsize(), tcsetwinsize() as suggested by @yuripv [ style(9) ].

sys/ttycom.h contains the definition of struct winsize needed for tcgetwinsize() and tcsetwinsize(); I have moved it to the protected block right before the tcgetwinsize() and the tcsetwinsize() declarations. Please compare that with the NetBSD header: https://github.com/NetBSD/src/blob/trunk/sys/sys/termios.h. In fact, both the NetBSD and the OpenBSD versions of termios.h only have sys/ttydefaults.h in the last block after the #endif /* !_TERMIOS_H_ */: