Hi Michael,
I'm fixing the example, and I trying to see if I can remove some of the
headers with the change. However, it's difficult to find that for sure,
at least from the manual pages alone. I think that's one of the biggest
inconsistencies in the pages and I'd like to fix that some day.
Also, I'll resend the old patch documenting off64_t in
system_data_types(7), given that this interface uses it.
For the SYNOPSIS sections of man2 and man3,
I'll try to have a single header,
and if there are some other headers needed (for type definitions, or
other), I'll add a comment to all of them, so that it's clear why each
header is needed.
See stat(2) as an example of what I don't like:
[[
SYNOPSIS
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
int stat(const char *pathname, struct stat *statbuf);
int fstat(int fd, struct stat *statbuf);
int lstat(const char *pathname, struct stat *statbuf);
#include <fcntl.h> /* Definition of AT_* constants */
#include <sys/stat.h>
int fstatat(int dirfd, const char *pathname, struct stat *statbuf,
int flags);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
lstat():
/* glibc 2.19 and earlier */ _BSD_SOURCE
|| /* Since glibc 2.20 */ _DEFAULT_SOURCE
|| _XOPEN_SOURCE >= 500
|| /* Since glibc 2.10: */ _POSIX_C_SOURCE >= 200112L
fstatat():
Since glibc 2.10:
_POSIX_C_SOURCE >= 200809L
Before glibc 2.10:
_ATFILE_SOURCE
]]
Why should one include all of those headers?
Which has the function definition?
And what do the others provide?
Cheers,
Alex
On 12/31/20 9:58 AM, Michael Kerrisk (man-pages) wrote:
> Hi Alex,
>
> On 12/31/20 12:20 AM, Alejandro Colomar (man-pages) wrote:
>>
>>
>> On 12/30/20 11:43 PM, Michael Kerrisk (man-pages) wrote:
>>> Hi Alex,
>>>
>>> On 12/30/20 10:41 PM, Alejandro Colomar wrote:
>>>> Glibc uses 'off64_t' instead of 'loff_t'.
>>>
>>> Okay.
>>>
>>>> This patch doesn't change the types in the code example,
>>>> because it uses the Linux syscall, and not the glibc wrapper.
>>>
>>> I think the example probably also needs fixing then. There's
>>> no longer a need for syscall(2) in this example, I think.
>>
>> Hi Michael,
>>
>> I thought the same, but glibc 2.26 is still supported,
>> and lacks the wrapper.
>> Would you change it already?
>
> Yes.
>
> Thanks,
>
> Michael
>
>
