Re: pg_amcheck contrib application

On Sat, Mar 13, 2021 at 10:51:27AM -0800, Mark Dilger wrote:
> > On Mar 13, 2021, at 10:46 AM, Noah Misch <noah(at)leadboat(dot)com> wrote:
> > On Fri, Mar 12, 2021 at 05:04:09PM -0800, Mark Dilger wrote:
> >>> On Mar 12, 2021, at 3:24 PM, Mark Dilger <mark(dot)dilger(at)enterprisedb(dot)com> wrote:
> >>> and the second deals with an apparent problem with IPC::Run shell expanding an asterisk on some platforms but not others. That second one, if true, seems like a problem with scope beyond the pg_amcheck project, as TestLib::command_checks_all uses IPC::Run, and it would be desirable to have consistent behavior across platforms.
> >
> >>> One of pg_amcheck's regression tests was passing an asterisk through
> >>> TestLib's command_checks_all() command, which gets through to
> >>> pg_amcheck without difficulty on most platforms, but appears to get
> >>> shell expanded on Windows (jacana) and AIX (hoverfly).
> >
> > For posterity, I can't reproduce this on hoverfly. The suite fails the same
> > way at f371a4c and f371a4c^. More-recently (commit 58f5749), the suite passes
> > even after reverting f371a4c. Self-contained IPC::Run usage also does not
> > corroborate the theory:
> >
> > [nm(at)power8-aix 8:0 2021-03-13T18:32:23 clean 0]$ perl -MIPC::Run -e 'IPC::Run::run "printf", "%s\n", "*"'
> > *
> > [nm(at)power8-aix 8:0 2021-03-13T18:32:29 clean 0]$ perl -MIPC::Run -e 'IPC::Run::run "sh", "-c", "printf %s\\\\n *"'
> > COPYRIGHT
> > GNUmakefile.in
> > HISTORY
> > Makefile
> > README
> > README.git
> > aclocal.m4
> > config
> > configure
> > configure.ac
> > contrib
> > doc
> > src

> The reason I suspected that passing the '*' through IPC::Run had to do with the error that pg_amcheck gave. It complained that too many arguments where being passed to it, and that the first such argument was "pg_amcheck.c". There's no reason pg_amcheck should know it's source file name, nor that the regression test should know that, which suggested that the asterisk was being shell expanded within the src/bin/pg_amcheck/ directory and the file listing was being passed into pg_amcheck as arguments.

I agree. I can reproduce the problem on Windows. Commit f371a4c fixed
http://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=fairywren&dt=2021-03-12%2020%3A12%3A44
and I see logs of that kind of failure only on fairywren and jacana.