Re: [PATCH] close_range.2: Add _GNU_SOURCE and unistd.h to SYNOPSIS

[Mark Wielaard <mark@klomp.org>]

Hi Alejandro,

On Sun, Feb 11, 2024 at 07:49:53PM +0100, Alejandro Colomar wrote:
> It seems this page was written when there was still no wrapper in libc.
> 
> But I see that Michael and I did mention there's now a wrapper in glibc:
> [...] 
> Both of those commits forgot to update the SYNOPSIS.  So, please add the
> following tags to your commit message:
> 
> Fixes: 71a62d6c3c56 ("close_range.2: Glibc added a wrapper recently")
> Fixes: c2356ba085ed ("close_range.2: Glibc 2.34 has added a close_range() wrapper")

I missed thos, will add the Fixes: to v2.

> >  .P
> >  .BI "int close_range(unsigned int " first ", unsigned int " last ,
> >  .BI "                unsigned int " flags );
> 
> And I notice the glibc wrapper is slightly different from the Linux
> kernel system call:
> 
> 	$ grepc close_range /usr/include/
> 	/usr/include/unistd.h:extern int close_range (unsigned int __fd, unsigned int __max_fd,
> 				int __flags) __THROW;
> 
> 
> 	$ grepc -tfl close_range ~/src/linux/linux/master/
> 	/home/alx/src/linux/linux/master/include/linux/syscalls.h:asmlinkage long sys_close_range(unsigned int fd, unsigned int max_fd,
> 					unsigned int flags);
> 	/home/alx/src/linux/linux/master/fs/open.c:SYSCALL_DEFINE3(close_range, unsigned int, fd, unsigned int, max_fd,
> 			unsigned int, flags)
> 	{
> 		return __close_range(fd, max_fd, flags);
> 	}
> 
> The third parameter is an 'int' in glibc.  Please also update that.

Will do. I see freebsd also uses int for flags.

I also noted just now that the example code still uses
syscall(SYS_close_range, 3, ~0U, 0)
even though it defines _GNU_SOURCE and includes unistd.h.
Will also fix that for v2.

Cheers,

Mark