Re: [PATCH v3] ctime.3: EXAMPLES: Add example program
From: Vincent Lefevre <hidden>
Date: 2024-08-23 08:00:17
On 2024-08-23 15:26:04 +0800, Xi Ruoyao wrote:
On Fri, 2024-08-23 at 09:02 +0200, Alejandro Colomar wrote:quoted
Is mktime(3) allowed to return -1 and set EOVERFLOW on a successful call? RETURN VALUE The mktime() function shall return the specified time since the Epoch encoded as a value of type time_t. If the time since the Epoch cannot be represented, the function shall return the value (time_t)-1 and set errno to indicate the error.For mktime the standard only says "return (time_t)-1." It does not mention errno at all. And the standard also says: The value of errno may be set to nonzero by a library function call whether or not there is an error, provided the use of errno is not documented in the description of the function in this document.quoted
Then I think the API is completely broken. How should we check for errors after a mktime(3) call?Maybe, special case if tm contains Dec 31 1969 23:59:59 UTC... But it's just stupid.quoted
If this is so, let me file a glibc bug requesting a fix of the API, adding a promise that on success, errno will remain unset.It's a bug in the standard, not glibc. And the standard has deprecated it anyway. https://www.open-std.org/JTC1/SC22/WG14/www/docs/n2566.pdf
I can see only asctime and ctime mentioned there, not mktime. So mktime isn't deprecated, is it? -- Vincent Lefèvre [off-list ref] - Web: <https://www.vinc17.net/> 100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/> Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)