check_disk_space: handle relative symlinks for the WAL directory #142
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If the WAL directory (pg_xlog or pg_wal) resolves to a symbolic link,
e.g. "../some-wal-dir", the check fails with an error like:
This patch checks for a relative symlink and extracts the actual WAL directory
using abs_path().
Not sure if it's feasible to add a test for this, if it is please let me know.