Re: pgsql: Add PSQL_WATCH_PAGER for psql's \watch command.

Thomas Munro <thomas(dot)munro(at)gmail(dot)com> writes:
> On Tue, Jul 13, 2021 at 1:09 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> That won't help as-is, because it *does* have sigwait, just not with
>> the POSIX API. thread_test.c does this:
>>
>> /* Test for POSIX.1c 2-arg sigwait() and fail on single-arg version */
>> #include <signal.h>
>> int sigwait(const sigset_t *set, int *sig);
>>
>> which perhaps should be pulled out of there and moved to the
>> configure script proper.

> Ah, I see. I'll have a crack at that after lunch.

Huh ... gaur did this:

/usr/ccs/bin/ld: Unsatisfied symbols:
sigwait (code)

which is not what I was expecting, because there is a definition for
sigwait in /usr/include (though not in a header file we use). It must
be in some add-on library instead of libc.

However, wrasse did this:

"/export/home/nm/farm/studio64v12_6/HEAD/pgsql.build/../pgsql/src/bin/psql/command.c", line 5062: prototype mismatch: 2 args passed, 1 expected
cc: acomp failed for /export/home/nm/farm/studio64v12_6/HEAD/pgsql.build/../pgsql/src/bin/psql/command.c

which I was expecting even less. Evidently, prehistoric HPUX is not the
only platform still using the pre-POSIX API for this function. So we
really do need the full configure check.

regards, tom lane