[PATCH 1/2] system_data_types.7: Document size_t

[Alejandro Colomar]

Hello Florian,

On 2020-09-18 16:34, Florian Weimer wrote:
 > * Alejandro Colomar via Libc-alpha:
 >
 >> +Used for a count of bytes.  It is the result of the
 >> +.I sizeof
 >> +operator.
 >> +According to the C language standard,
 >> +it shall be an unsigned integer type
 >> +capable of storing values in the range [0,
 >> +.BR SIZE_MAX ].
 >
 > Thanks for working on this.

:-)

 > Maybe add that this commonly maps to unsigned int or unsigned long, and

I thought the same in the beginning,
but then Michael convinced me to not do it.

On 2020-09-13 22:20, Michael Kerrisk (man-pages) wrote:
 >>>> Is it a 32-bit or 64-bit or may vary? Is it signed or unsigned?
 >>> POSIX doesn't specify, I think.>
 >>> One other thing the page should show of course is definition of the
 >>> structure types.
 >> Yes.
 >>
 >>
 >>      timer_t     <time.h> or <sys/types.h>
 >>          POSIX timer ID.
 >>
 >>          typedef void *timer_t;
 > Here I would *not* show these kinds of typedefs. The point is
 > that these types should be treated as being somewhat unknown
 > (e.g., for casts in printf()). Here, I think instead maybe we
 > just have a statement that POSIX makes no specific requirements
 > for the representation of this type.

I think I prefer to leave it opaque, showing only the requirements
that POSIX and C make.

There's really not much gain (basically uint and ulong cover most of the
possibilities; and still it's not a guarantee).
And readers might write non-portable code because of reading that.

On 2020-09-18 16:34, Florian Weimer wrote:
 > that the length modifier for printf and scanf is z, commently used as
 > %zu or %zx (%zd is for ssize_t).

Good idea.

Would you prefer that, or just refer to printf(3) in See also?.

 >
 > Florian
 >

Thanks,

Alex