BUG #6726: pg_dump - ftell mismatch when using -Fc and split

The following bug has been logged on the website:

Bug reference: 6726
Logged by: Andy Gumbrecht
Email address: andy(dot)gumbrecht(at)orprovision(dot)com
PostgreSQL version: 9.1.4
Operating system: Windows 7 32 or 64 bit
Description:

Using:

"D:\pg\bin\pg_dump.exe" -F c -E utf8 -U postgres -w unit_Production |
"D:\pg\bin\split.exe" -b 256m - "D:\BAK\Production\production-"

The following error is produced:

pg_dump: [custom archiver] WARNING: ftell mismatch with expected position --
ftell used

I guess that the -F c option requires a physical file and attempts to seek,
which fails.

If this is the case then using pg_dump -F c should fail noisily when the -f
option is not present.