Re: fix pg_mkdir_p to tolerate concurrent directory creation

On 2026-06-18 Th 10:24 AM, Tom Lane wrote:
> Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
>> While working on the pytest stuff, I found this issue when making it
>> work on Windows, but the issue can exist everywhere. pg_mkdir_p can fail
>> if there is a concurrent directory creation.
> This bit:
>
> + if (errno != EEXIST || stat(path, &sb) != 0 || !S_ISDIR(sb.st_mode))
> + {
> + retval = -1;
> + break;
> + }
>
> looks like it could corrupt the reported errno, ie stat() could
> overwrite what mkdir() reported.
>
>

Oh, good catch, thanks! Here's a revised patch.

cheers

andrew

--
Andrew Dunstan
EDB: https://www.enterprisedb.com