pg_upgrade and log file output on Windows

Has anyone successfully used pg_upgrade 9.0 with -l (log) on Windows?

I received a private email bug report that pg_upgrade 9.0 does not work
with the -l/log option on Windows. The error is:

Analyzing all rows in the new cluster
""c:/MinGW/msys/1.0/home/edb/inst/bin/vacuumdb" --port 55445 --username "edb" --all --analyze
>> c:/MinGW/msys/1.0/home/edb/auxschedule/test.log 2>&1"
The process cannot access the file because it is being used by another
process.

What has me confused is this same code exists in pg_migrator, which was
fixed to work with -l on Windows by Hiroshi Saito with this change:

/*
* On Win32, we can't send both server output and pg_ctl output
* to the same file because we get the error:
* "The process cannot access the file because it is being used by another process."
* so we have to send pg_ctl output to 'nul'.
*/
sprintf(cmd, SYSTEMQUOTE "\"%s/pg_ctl\" -l \"%s\" -D \"%s\" "
"-o \"-p %d -c autovacuum=off -c autovacuum_freeze_max_age=2000000000\" "
"start >> \"%s\" 2>&1" SYSTEMQUOTE,
bindir, ctx->logfile, datadir, port,
#ifndef WIN32
ctx->logfile);
#else
DEVNULL);
#endif

The fix was not to use the same log file and output file for pg_ctl.
But as you can see, the pg_ctl and vacuumdb code is unchanged:

prep_status(ctx, "Analyzing all rows in the new cluster");
exec_prog(ctx, true,
SYSTEMQUOTE "\"%s/vacuumdb\" --port %d --username \"%s\" "
"--all --analyze >> %s 2>&1" SYSTEMQUOTE,
ctx->new.bindir, ctx->new.port, ctx->user, ctx->logfile);

I can't figure out of there is something odd about this user's setup or
if there is a bug in pg_upgrade with -l on Windows.

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ It's impossible for everything to be true. +