From 865ebc9e0c433ca00dcdc97dfb5721b8475aa0e9 Mon Sep 17 00:00:00 2001
From: Hao Wu <gfphoenix78@gmail.com>
Date: Tue, 26 May 2026 02:21:52 +0000
Subject: [PATCH] Fix greenplum_path.sh GPHOME resolution under relative
 symlinks

When GPHOME is reached via a symlink whose target is stored as a
relative path (e.g. /opt/database -> database-2.1.0), the previous
logic ran a bare `readlink` on the script's directory and accepted
the link target verbatim.  `readlink` returns the symlink's target
string as-is; for a relative target this leaves GPHOME as a relative
path, so PYTHONPATH becomes `database-2.1.0/lib/python` and gpstart
fails with ModuleNotFoundError: No module named 'gppylib' the moment
the shell's cwd is anything other than the symlink's parent.

Replace the symlink-vs-not branch with a single `pwd -P`, which
resolves every symlink component and returns the canonical absolute
path regardless of how the user reached the directory.  This also
removes the unnecessary `[ -L ... ]` test and the dependency on GNU
readlink semantics.
---
 gpMgmt/bin/generate-cloudberry-env.sh | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/gpMgmt/bin/generate-cloudberry-env.sh b/gpMgmt/bin/generate-cloudberry-env.sh
index 7f1f9074efc..0eca71b4884 100755
--- a/gpMgmt/bin/generate-cloudberry-env.sh
+++ b/gpMgmt/bin/generate-cloudberry-env.sh
@@ -17,13 +17,15 @@ fi
 if test -z "$SCRIPT_PATH"; then
     echo "The shell cannot be identified. \$GPHOME may not be set correctly." >&2
 fi
-SCRIPT_DIR="$(cd "$(dirname "${SCRIPT_PATH}")" >/dev/null 2>&1 && pwd)"
 
-if [ ! -L "${SCRIPT_DIR}" ]; then
-    GPHOME=${SCRIPT_DIR}
-else
-    GPHOME=$(readlink "${SCRIPT_DIR}")
-fi
+# downstream PATH / PYTHONPATH / LD_LIBRARY_PATH derivations stay valid
+# even when GPHOME is reached via a symlink whose target is a relative
+# path (e.g. /opt/database -> database-2.1.0).  `pwd -P` resolves every
+# symlink component, returning the physical absolute path.  This replaces
+# an earlier branch that ran bare `readlink` on the script's directory,
+# which would return the symlink target verbatim and break with relative
+# targets (PYTHONPATH became relative, gppylib import failed).
+GPHOME="$(cd "$(dirname "${SCRIPT_PATH}")" >/dev/null 2>&1 && pwd -P)"
 EOF
 
 cat <<"EOF"