detecting binary backup in progress

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I can check for the presence of $PGDATA/backup_label in order to detect
a backup in progress (i.e. pg_start_backup() has been run and
pg_stop_backup() has not yet been run).

However there is a period of time after pg_start_backup() is first
executed to when it completes, during which backup_label file does not
exist yet, but the backup has essentially been started. Is there any
way to detect this state?

Thanks,

Joe

- --
Joe Conway
credativ LLC: http://www.credativ.us
Linux, PostgreSQL, and general Open Source
Training, Service, Consulting, & 24x7 Support
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