[SOLVED] man pages declarations

marijan · 12-17-2023, 03:41 AM

Code:

void qsort(void base[.size * .nmemb], size_t nmemb, size_t size, int (*compar)(const void [.size], const void [.size]));
void qsort(void *base, size_t nmemb, size_t size, int (*compar)(const void *, const void *));

The first line is delaclaration of qsort stdlib function in Debian.
The second line is from NetBSD. NetBSD looks like an old school.
I didn't notice when linux started with new declaration.
But I don't know why it is so? And where it is explained?
What are dots in .size and .nmemb?

frankbell · 12-17-2023, 08:16 PM

You might start with man man.

lvm_ · 12-18-2023, 12:57 AM

Just like all other files in FOSS projects, man pages are stored in publicly available version control systems where you can see change history for a file and, hopefully, comments giving reasons for changes. All you have to do is use your google-fu to locate it.

marijan · 12-18-2023, 02:58 AM

Quote:

Originally Posted by lvm_

Just like all other files in FOSS projects, man pages are stored in publicly available version control systems where you can see change history for a file and, hopefully, comments giving reasons for changes. All you have to do is use your google-fu to locate it.

In other words, both of you have no slightest idea.
mam man is a universal poor ignorant answer, as well as whatever-fu. Thanks.

Petri Kaukasoina · 12-18-2023, 03:47 AM

Like lvm_ wrote, the Linux man pages are in git. A handy web page: https://git.kernel.org/pub/scm/docs/...man-pages.git/. qsort.3 man page has seen these commits: https://git.kernel.org/pub/scm/docs/...g/man3/qsort.3 There is a commit 2022-11-10 'Various pages: SYNOPSIS: Use VLA syntax in 'void *' function parameters': https://git.kernel.org/pub/scm/docs/...8a640f034fea70

The explanation:

Code:

Use VLA syntax also for void *, even if it's a bit more weird.

Link: <https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2611.htm>
Cc: Ingo Schwarze <schwarze@openbsd.org>
Cc: JeanHeyd Meneide <wg14@soasis.org>
Cc: Martin Uecker <uecker@tugraz.at>
Cc: <gcc@gcc.gnu.org>
Signed-off-by: Alex Colomar <alx.manpages@gmail.com>

About the VLA syntax in the https link above:

Quote:

Additional Principle for C23
At the WG 14 meeting in London, England, in April, 2016, the previous principles were reviewed, and the following was added:

15. Application Programming Interfaces (APIs) should be self-documenting when possible. In particular, the order of parameters in function declarations should be arranged such that the size of an array appears before the array. The purpose is to allow Variable-Length Array (VLA) notation to be used. This not only makes the code's purpose clearer to human readers, but also makes static analysis easier. Any new APIs added to the Standard should take this into consideration.

marijan · 12-18-2023, 04:04 AM

Quote:

Originally Posted by Petri Kaukasoina

Like lvm_ wrote, the Linux man pages are in git. A handy web page: https://git.kernel.org/pub/scm/docs/...man-pages.git/. qsort.3 man page has seen these commits: https://git.kernel.org/pub/scm/docs/...g/man3/qsort.3 There is a commit 2022-11-10 'Various pages: SYNOPSIS: Use VLA syntax in 'void *' function parameters': https://git.kernel.org/pub/scm/docs/...8a640f034fea70

The explanation:

Code:

Use VLA syntax also for void *, even if it's a bit more weird.

Link: <https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2611.htm>
Cc: Ingo Schwarze <schwarze@openbsd.org>
Cc: JeanHeyd Meneide <wg14@soasis.org>
Cc: Martin Uecker <uecker@tugraz.at>
Cc: <gcc@gcc.gnu.org>
Signed-off-by: Alex Colomar <alx.manpages@gmail.com>

About the VLA syntax in the https link above:

Thank You.

lvm_ · 12-19-2023, 12:45 AM

Quote:

Originally Posted by marijan

In other words, both of you have no slightest idea.

Try to teach a hungry man to fish, and as so often, he demonstrates his indolence in a rude manner. And someone meekly give him a fish...