diff --git a/contrib/dblink/input/paths.source b/contrib/dblink/input/paths.source
index 881a65314f..30403d9d5f 100644
--- a/contrib/dblink/input/paths.source
+++ b/contrib/dblink/input/paths.source
@@ -1,14 +1,23 @@
 -- Initialization that requires path substitution.
 
+-- directory paths and dlsuffix are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
+\getenv libdir PG_LIBDIR
+\getenv dlsuffix PG_DLSUFFIX
+
+\set regresslib :libdir '/regress' :dlsuffix
+
 CREATE FUNCTION setenv(text, text)
    RETURNS void
-   AS '@libdir@/regress@DLSUFFIX@', 'regress_setenv'
+   AS :'regresslib', 'regress_setenv'
    LANGUAGE C STRICT;
 
 CREATE FUNCTION wait_pid(int)
    RETURNS void
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT;
 
+\set path :abs_srcdir '/'
+\set fnbody 'SELECT setenv(''PGSERVICEFILE'', ' :'path' ' || $1)'
 CREATE FUNCTION set_pgservicefile(text) RETURNS void LANGUAGE SQL
-    AS $$SELECT setenv('PGSERVICEFILE', '@abs_srcdir@/' || $1)$$;
+    AS :'fnbody';
diff --git a/contrib/dblink/output/paths.source b/contrib/dblink/output/paths.source
index 8ed95e1f78..d09b169b19 100644
--- a/contrib/dblink/output/paths.source
+++ b/contrib/dblink/output/paths.source
@@ -1,11 +1,18 @@
 -- Initialization that requires path substitution.
+-- directory paths and dlsuffix are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
+\getenv libdir PG_LIBDIR
+\getenv dlsuffix PG_DLSUFFIX
+\set regresslib :libdir '/regress' :dlsuffix
 CREATE FUNCTION setenv(text, text)
    RETURNS void
-   AS '@libdir@/regress@DLSUFFIX@', 'regress_setenv'
+   AS :'regresslib', 'regress_setenv'
    LANGUAGE C STRICT;
 CREATE FUNCTION wait_pid(int)
    RETURNS void
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT;
+\set path :abs_srcdir '/'
+\set fnbody 'SELECT setenv(''PGSERVICEFILE'', ' :'path' ' || $1)'
 CREATE FUNCTION set_pgservicefile(text) RETURNS void LANGUAGE SQL
-    AS $$SELECT setenv('PGSERVICEFILE', '@abs_srcdir@/' || $1)$$;
+    AS :'fnbody';
diff --git a/contrib/file_fdw/input/file_fdw.source b/contrib/file_fdw/input/file_fdw.source
index 45b728eeb3..0ea8b14508 100644
--- a/contrib/file_fdw/input/file_fdw.source
+++ b/contrib/file_fdw/input/file_fdw.source
@@ -2,6 +2,9 @@
 -- Test foreign-data wrapper file_fdw.
 --
 
+-- directory paths are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
+
 -- Clean up in case a prior regression run failed
 SET client_min_messages TO 'warning';
 DROP ROLE IF EXISTS regress_file_fdw_superuser, regress_file_fdw_user, regress_no_priv_user;
@@ -14,6 +17,22 @@ CREATE ROLE regress_no_priv_user LOGIN;                 -- has priv but no user
 -- Install file_fdw
 CREATE EXTENSION file_fdw;
 
+-- create function to filter unstable results of EXPLAIN
+CREATE FUNCTION explain_filter(text) RETURNS setof text
+LANGUAGE plpgsql AS
+$$
+declare
+    ln text;
+begin
+    for ln in execute $1
+    loop
+        -- Remove the path portion of foreign file names
+        ln := regexp_replace(ln, 'Foreign File: .*/([a-z.]+)$', 'Foreign File: .../\1');
+        return next ln;
+    end loop;
+end;
+$$;
+
 -- regress_file_fdw_superuser owns fdw-related objects
 SET ROLE regress_file_fdw_superuser;
 CREATE SERVER file_server FOREIGN DATA WRAPPER file_fdw;
@@ -61,33 +80,39 @@ CREATE FOREIGN TABLE tbl () SERVER file_server OPTIONS (format 'csv', null '
 ');       -- ERROR
 CREATE FOREIGN TABLE tbl () SERVER file_server;  -- ERROR
 
+\set filename :abs_srcdir '/data/agg.data'
 CREATE FOREIGN TABLE agg_text (
 	a	int2 CHECK (a >= 0),
 	b	float4
 ) SERVER file_server
-OPTIONS (format 'text', filename '@abs_srcdir@/data/agg.data', delimiter '	', null '\N');
+OPTIONS (format 'text', filename :'filename', delimiter '	', null '\N');
 GRANT SELECT ON agg_text TO regress_file_fdw_user;
+
+\set filename :abs_srcdir '/data/agg.csv'
 CREATE FOREIGN TABLE agg_csv (
 	a	int2,
 	b	float4
 ) SERVER file_server
-OPTIONS (format 'csv', filename '@abs_srcdir@/data/agg.csv', header 'true', delimiter ';', quote '@', escape '"', null '');
+OPTIONS (format 'csv', filename :'filename', header 'true', delimiter ';', quote '@', escape '"', null '');
 ALTER FOREIGN TABLE agg_csv ADD CHECK (a >= 0);
+
+\set filename :abs_srcdir '/data/agg.bad'
 CREATE FOREIGN TABLE agg_bad (
 	a	int2,
 	b	float4
 ) SERVER file_server
-OPTIONS (format 'csv', filename '@abs_srcdir@/data/agg.bad', header 'true', delimiter ';', quote '@', escape '"', null '');
+OPTIONS (format 'csv', filename :'filename', header 'true', delimiter ';', quote '@', escape '"', null '');
 ALTER FOREIGN TABLE agg_bad ADD CHECK (a >= 0);
 
 -- per-column options tests
+\set filename :abs_srcdir '/data/text.csv'
 CREATE FOREIGN TABLE text_csv (
     word1 text OPTIONS (force_not_null 'true'),
     word2 text OPTIONS (force_not_null 'off'),
     word3 text OPTIONS (force_null 'true'),
     word4 text OPTIONS (force_null 'off')
 ) SERVER file_server
-OPTIONS (format 'text', filename '@abs_srcdir@/data/text.csv', null 'NULL');
+OPTIONS (format 'text', filename :'filename', null 'NULL');
 SELECT * FROM text_csv; -- ERROR
 ALTER FOREIGN TABLE text_csv OPTIONS (SET format 'csv');
 \pset null _null_
@@ -119,7 +144,7 @@ SELECT * FROM agg_bad;               -- ERROR
 
 -- misc query tests
 \t on
-EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_csv;
+SELECT explain_filter('EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_csv');
 \t off
 PREPARE st(int) AS SELECT * FROM agg_csv WHERE a = $1;
 EXECUTE st(100);
@@ -143,12 +168,12 @@ COPY agg_csv FROM STDIN;
 
 -- constraint exclusion tests
 \t on
-EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_csv WHERE a < 0;
+SELECT explain_filter('EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_csv WHERE a < 0');
 \t off
 SELECT * FROM agg_csv WHERE a < 0;
 SET constraint_exclusion = 'on';
 \t on
-EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_csv WHERE a < 0;
+SELECT explain_filter('EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_csv WHERE a < 0');
 \t off
 SELECT * FROM agg_csv WHERE a < 0;
 RESET constraint_exclusion;
@@ -170,14 +195,17 @@ DROP TABLE agg;
 -- declarative partitioning tests
 SET ROLE regress_file_fdw_superuser;
 CREATE TABLE pt (a int, b text) partition by list (a);
+\set filename :abs_srcdir '/data/list1.csv'
 CREATE FOREIGN TABLE p1 partition of pt for values in (1) SERVER file_server
-OPTIONS (format 'csv', filename '@abs_srcdir@/data/list1.csv', delimiter ',');
+OPTIONS (format 'csv', filename :'filename', delimiter ',');
 CREATE TABLE p2 partition of pt for values in (2);
 SELECT tableoid::regclass, * FROM pt;
 SELECT tableoid::regclass, * FROM p1;
 SELECT tableoid::regclass, * FROM p2;
-COPY pt FROM '@abs_srcdir@/data/list2.bad' with (format 'csv', delimiter ','); -- ERROR
-COPY pt FROM '@abs_srcdir@/data/list2.csv' with (format 'csv', delimiter ',');
+\set filename :abs_srcdir '/data/list2.bad'
+COPY pt FROM :'filename' with (format 'csv', delimiter ','); -- ERROR
+\set filename :abs_srcdir '/data/list2.csv'
+COPY pt FROM :'filename' with (format 'csv', delimiter ',');
 SELECT tableoid::regclass, * FROM pt;
 SELECT tableoid::regclass, * FROM p1;
 SELECT tableoid::regclass, * FROM p2;
@@ -190,8 +218,9 @@ SELECT tableoid::regclass, * FROM p2;
 DROP TABLE pt;
 
 -- generated column tests
+\set filename :abs_srcdir '/data/list1.csv'
 CREATE FOREIGN TABLE gft1 (a int, b text, c text GENERATED ALWAYS AS ('foo') STORED) SERVER file_server
-OPTIONS (format 'csv', filename '@abs_srcdir@/data/list1.csv', delimiter ',');
+OPTIONS (format 'csv', filename :'filename', delimiter ',');
 SELECT a, c FROM gft1;
 DROP FOREIGN TABLE gft1;
 
@@ -204,7 +233,7 @@ SET ROLE regress_no_priv_user;
 SELECT * FROM agg_text ORDER BY a;   -- ERROR
 SET ROLE regress_file_fdw_user;
 \t on
-EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_text WHERE a > 0;
+SELECT explain_filter('EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_text WHERE a > 0');
 \t off
 -- file FDW allows foreign tables to be accessed without user mapping
 DROP USER MAPPING FOR regress_file_fdw_user SERVER file_server;
diff --git a/contrib/file_fdw/output/file_fdw.source b/contrib/file_fdw/output/file_fdw.source
index 52b4d5f1df..891146fef3 100644
--- a/contrib/file_fdw/output/file_fdw.source
+++ b/contrib/file_fdw/output/file_fdw.source
@@ -1,6 +1,8 @@
 --
 -- Test foreign-data wrapper file_fdw.
 --
+-- directory paths are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
 -- Clean up in case a prior regression run failed
 SET client_min_messages TO 'warning';
 DROP ROLE IF EXISTS regress_file_fdw_superuser, regress_file_fdw_user, regress_no_priv_user;
@@ -10,6 +12,21 @@ CREATE ROLE regress_file_fdw_user LOGIN;                -- has priv and user map
 CREATE ROLE regress_no_priv_user LOGIN;                 -- has priv but no user mapping
 -- Install file_fdw
 CREATE EXTENSION file_fdw;
+-- create function to filter unstable results of EXPLAIN
+CREATE FUNCTION explain_filter(text) RETURNS setof text
+LANGUAGE plpgsql AS
+$$
+declare
+    ln text;
+begin
+    for ln in execute $1
+    loop
+        -- Remove the path portion of foreign file names
+        ln := regexp_replace(ln, 'Foreign File: .*/([a-z.]+)$', 'Foreign File: .../\1');
+        return next ln;
+    end loop;
+end;
+$$;
 -- regress_file_fdw_superuser owns fdw-related objects
 SET ROLE regress_file_fdw_superuser;
 CREATE SERVER file_server FOREIGN DATA WRAPPER file_fdw;
@@ -77,32 +94,36 @@ CREATE FOREIGN TABLE tbl () SERVER file_server OPTIONS (format 'csv', null '
 ERROR:  COPY null representation cannot use newline or carriage return
 CREATE FOREIGN TABLE tbl () SERVER file_server;  -- ERROR
 ERROR:  either filename or program is required for file_fdw foreign tables
+\set filename :abs_srcdir '/data/agg.data'
 CREATE FOREIGN TABLE agg_text (
 	a	int2 CHECK (a >= 0),
 	b	float4
 ) SERVER file_server
-OPTIONS (format 'text', filename '@abs_srcdir@/data/agg.data', delimiter '	', null '\N');
+OPTIONS (format 'text', filename :'filename', delimiter '	', null '\N');
 GRANT SELECT ON agg_text TO regress_file_fdw_user;
+\set filename :abs_srcdir '/data/agg.csv'
 CREATE FOREIGN TABLE agg_csv (
 	a	int2,
 	b	float4
 ) SERVER file_server
-OPTIONS (format 'csv', filename '@abs_srcdir@/data/agg.csv', header 'true', delimiter ';', quote '@', escape '"', null '');
+OPTIONS (format 'csv', filename :'filename', header 'true', delimiter ';', quote '@', escape '"', null '');
 ALTER FOREIGN TABLE agg_csv ADD CHECK (a >= 0);
+\set filename :abs_srcdir '/data/agg.bad'
 CREATE FOREIGN TABLE agg_bad (
 	a	int2,
 	b	float4
 ) SERVER file_server
-OPTIONS (format 'csv', filename '@abs_srcdir@/data/agg.bad', header 'true', delimiter ';', quote '@', escape '"', null '');
+OPTIONS (format 'csv', filename :'filename', header 'true', delimiter ';', quote '@', escape '"', null '');
 ALTER FOREIGN TABLE agg_bad ADD CHECK (a >= 0);
 -- per-column options tests
+\set filename :abs_srcdir '/data/text.csv'
 CREATE FOREIGN TABLE text_csv (
     word1 text OPTIONS (force_not_null 'true'),
     word2 text OPTIONS (force_not_null 'off'),
     word3 text OPTIONS (force_null 'true'),
     word4 text OPTIONS (force_null 'off')
 ) SERVER file_server
-OPTIONS (format 'text', filename '@abs_srcdir@/data/text.csv', null 'NULL');
+OPTIONS (format 'text', filename :'filename', null 'NULL');
 SELECT * FROM text_csv; -- ERROR
 ERROR:  COPY force not null available only in CSV mode
 ALTER FOREIGN TABLE text_csv OPTIONS (SET format 'csv');
@@ -176,10 +197,10 @@ ERROR:  invalid input syntax for type real: "aaa"
 CONTEXT:  COPY agg_bad, line 3, column b: "aaa"
 -- misc query tests
 \t on
-EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_csv;
+SELECT explain_filter('EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_csv');
  Foreign Scan on public.agg_csv
    Output: a, b
-   Foreign File: @abs_srcdir@/data/agg.csv
+   Foreign File: .../agg.csv
 
 \t off
 PREPARE st(int) AS SELECT * FROM agg_csv WHERE a = $1;
@@ -226,11 +247,11 @@ COPY agg_csv FROM STDIN;
 ERROR:  cannot insert into foreign table "agg_csv"
 -- constraint exclusion tests
 \t on
-EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_csv WHERE a < 0;
+SELECT explain_filter('EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_csv WHERE a < 0');
  Foreign Scan on public.agg_csv
    Output: a, b
    Filter: (agg_csv.a < 0)
-   Foreign File: @abs_srcdir@/data/agg.csv
+   Foreign File: .../agg.csv
 
 \t off
 SELECT * FROM agg_csv WHERE a < 0;
@@ -240,7 +261,7 @@ SELECT * FROM agg_csv WHERE a < 0;
 
 SET constraint_exclusion = 'on';
 \t on
-EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_csv WHERE a < 0;
+SELECT explain_filter('EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_csv WHERE a < 0');
  Result
    Output: a, b
    One-Time Filter: false
@@ -295,8 +316,9 @@ DROP TABLE agg;
 -- declarative partitioning tests
 SET ROLE regress_file_fdw_superuser;
 CREATE TABLE pt (a int, b text) partition by list (a);
+\set filename :abs_srcdir '/data/list1.csv'
 CREATE FOREIGN TABLE p1 partition of pt for values in (1) SERVER file_server
-OPTIONS (format 'csv', filename '@abs_srcdir@/data/list1.csv', delimiter ',');
+OPTIONS (format 'csv', filename :'filename', delimiter ',');
 CREATE TABLE p2 partition of pt for values in (2);
 SELECT tableoid::regclass, * FROM pt;
  tableoid | a |  b  
@@ -317,10 +339,12 @@ SELECT tableoid::regclass, * FROM p2;
 ----------+---+---
 (0 rows)
 
-COPY pt FROM '@abs_srcdir@/data/list2.bad' with (format 'csv', delimiter ','); -- ERROR
+\set filename :abs_srcdir '/data/list2.bad'
+COPY pt FROM :'filename' with (format 'csv', delimiter ','); -- ERROR
 ERROR:  cannot insert into foreign table "p1"
 CONTEXT:  COPY pt, line 2: "1,qux"
-COPY pt FROM '@abs_srcdir@/data/list2.csv' with (format 'csv', delimiter ',');
+\set filename :abs_srcdir '/data/list2.csv'
+COPY pt FROM :'filename' with (format 'csv', delimiter ',');
 SELECT tableoid::regclass, * FROM pt;
  tableoid | a |  b  
 ----------+---+-----
@@ -376,8 +400,9 @@ SELECT tableoid::regclass, * FROM p2;
 
 DROP TABLE pt;
 -- generated column tests
+\set filename :abs_srcdir '/data/list1.csv'
 CREATE FOREIGN TABLE gft1 (a int, b text, c text GENERATED ALWAYS AS ('foo') STORED) SERVER file_server
-OPTIONS (format 'csv', filename '@abs_srcdir@/data/list1.csv', delimiter ',');
+OPTIONS (format 'csv', filename :'filename', delimiter ',');
 SELECT a, c FROM gft1;
  a |   c    
 ---+--------
@@ -412,11 +437,11 @@ SELECT * FROM agg_text ORDER BY a;   -- ERROR
 ERROR:  permission denied for foreign table agg_text
 SET ROLE regress_file_fdw_user;
 \t on
-EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_text WHERE a > 0;
+SELECT explain_filter('EXPLAIN (VERBOSE, COSTS FALSE) SELECT * FROM agg_text WHERE a > 0');
  Foreign Scan on public.agg_text
    Output: a, b
    Filter: (agg_text.a > 0)
-   Foreign File: @abs_srcdir@/data/agg.data
+   Foreign File: .../agg.data
 
 \t off
 -- file FDW allows foreign tables to be accessed without user mapping
diff --git a/src/pl/plpgsql/src/input/plpgsql_copy.source b/src/pl/plpgsql/src/input/plpgsql_copy.source
index b7bcbb7d17..37f1fa132b 100644
--- a/src/pl/plpgsql/src/input/plpgsql_copy.source
+++ b/src/pl/plpgsql/src/input/plpgsql_copy.source
@@ -1,3 +1,11 @@
+-- directory paths are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
+\getenv abs_builddir PG_ABS_BUILDDIR
+
+-- set up file names to use
+\set srcfilename :abs_srcdir '/data/copy1.data'
+\set destfilename :abs_builddir '/results/copy1.data'
+
 CREATE TABLE copy1 (a int, b float);
 
 -- COPY TO/FROM not authorized from client.
@@ -24,38 +32,26 @@ $$;
 
 -- Valid cases
 -- COPY FROM
-DO LANGUAGE plpgsql $$
-BEGIN
-  COPY copy1 FROM '@abs_srcdir@/data/copy1.data';
-END;
-$$;
+\set dobody 'BEGIN COPY copy1 FROM ' :'srcfilename' '; END'
+DO LANGUAGE plpgsql :'dobody';
 SELECT * FROM copy1 ORDER BY 1;
 TRUNCATE copy1;
-DO LANGUAGE plpgsql $$
-BEGIN
-  EXECUTE 'COPY copy1 FROM ''@abs_srcdir@/data/copy1.data''';
-END;
-$$;
+\set cmd 'COPY copy1 FROM ' :'srcfilename'
+\set dobody 'BEGIN EXECUTE ' :'cmd' '; END'
+DO LANGUAGE plpgsql :'dobody';
 SELECT * FROM copy1 ORDER BY 1;
 
 -- COPY TO
 -- Copy the data externally once, then process it back to the table.
-DO LANGUAGE plpgsql $$
-BEGIN
-  COPY copy1 TO '@abs_builddir@/results/copy1.data';
-END;
-$$;
+\set dobody 'BEGIN COPY copy1 TO ' :'destfilename' '; END'
+DO LANGUAGE plpgsql :'dobody';
 TRUNCATE copy1;
-DO LANGUAGE plpgsql $$
-BEGIN
-  COPY copy1 FROM '@abs_builddir@/results/copy1.data';
-END;
-$$;
-DO LANGUAGE plpgsql $$
-BEGIN
-  EXECUTE 'COPY copy1 FROM ''@abs_builddir@/results/copy1.data''';
-END;
-$$;
+\set dobody 'BEGIN COPY copy1 FROM ' :'destfilename' '; END'
+DO LANGUAGE plpgsql :'dobody';
+
+\set cmd 'COPY copy1 FROM ' :'destfilename'
+\set dobody 'BEGIN EXECUTE ' :'cmd' '; END'
+DO LANGUAGE plpgsql :'dobody';
 
 SELECT * FROM copy1 ORDER BY 1;
 
diff --git a/src/pl/plpgsql/src/output/plpgsql_copy.source b/src/pl/plpgsql/src/output/plpgsql_copy.source
index 86e833d055..bc834be197 100644
--- a/src/pl/plpgsql/src/output/plpgsql_copy.source
+++ b/src/pl/plpgsql/src/output/plpgsql_copy.source
@@ -1,3 +1,9 @@
+-- directory paths are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
+\getenv abs_builddir PG_ABS_BUILDDIR
+-- set up file names to use
+\set srcfilename :abs_srcdir '/data/copy1.data'
+\set destfilename :abs_builddir '/results/copy1.data'
 CREATE TABLE copy1 (a int, b float);
 -- COPY TO/FROM not authorized from client.
 DO LANGUAGE plpgsql $$
@@ -30,11 +36,8 @@ ERROR:  cannot COPY to/from client in PL/pgSQL
 CONTEXT:  PL/pgSQL function inline_code_block line 3 at EXECUTE
 -- Valid cases
 -- COPY FROM
-DO LANGUAGE plpgsql $$
-BEGIN
-  COPY copy1 FROM '@abs_srcdir@/data/copy1.data';
-END;
-$$;
+\set dobody 'BEGIN COPY copy1 FROM ' :'srcfilename' '; END'
+DO LANGUAGE plpgsql :'dobody';
 SELECT * FROM copy1 ORDER BY 1;
  a |  b  
 ---+-----
@@ -44,11 +47,9 @@ SELECT * FROM copy1 ORDER BY 1;
 (3 rows)
 
 TRUNCATE copy1;
-DO LANGUAGE plpgsql $$
-BEGIN
-  EXECUTE 'COPY copy1 FROM ''@abs_srcdir@/data/copy1.data''';
-END;
-$$;
+\set cmd 'COPY copy1 FROM ' :'srcfilename'
+\set dobody 'BEGIN EXECUTE ' :'cmd' '; END'
+DO LANGUAGE plpgsql :'dobody';
 SELECT * FROM copy1 ORDER BY 1;
  a |  b  
 ---+-----
@@ -59,22 +60,14 @@ SELECT * FROM copy1 ORDER BY 1;
 
 -- COPY TO
 -- Copy the data externally once, then process it back to the table.
-DO LANGUAGE plpgsql $$
-BEGIN
-  COPY copy1 TO '@abs_builddir@/results/copy1.data';
-END;
-$$;
+\set dobody 'BEGIN COPY copy1 TO ' :'destfilename' '; END'
+DO LANGUAGE plpgsql :'dobody';
 TRUNCATE copy1;
-DO LANGUAGE plpgsql $$
-BEGIN
-  COPY copy1 FROM '@abs_builddir@/results/copy1.data';
-END;
-$$;
-DO LANGUAGE plpgsql $$
-BEGIN
-  EXECUTE 'COPY copy1 FROM ''@abs_builddir@/results/copy1.data''';
-END;
-$$;
+\set dobody 'BEGIN COPY copy1 FROM ' :'destfilename' '; END'
+DO LANGUAGE plpgsql :'dobody';
+\set cmd 'COPY copy1 FROM ' :'destfilename'
+\set dobody 'BEGIN EXECUTE ' :'cmd' '; END'
+DO LANGUAGE plpgsql :'dobody';
 SELECT * FROM copy1 ORDER BY 1;
  a |  b  
 ---+-----
diff --git a/src/test/regress/input/constraints.source b/src/test/regress/input/constraints.source
index 6bb7648321..458f805778 100644
--- a/src/test/regress/input/constraints.source
+++ b/src/test/regress/input/constraints.source
@@ -8,6 +8,9 @@
 --  - EXCLUDE clauses
 --
 
+-- directory paths are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
+
 --
 -- DEFAULT syntax
 --
@@ -239,11 +242,13 @@ CREATE TABLE COPY_TBL (x INT, y TEXT, z INT,
 	CONSTRAINT COPY_CON
 	CHECK (x > 3 AND y <> 'check failed' AND x < 7 ));
 
-COPY COPY_TBL FROM '@abs_srcdir@/data/constro.data';
+\set filename :abs_srcdir '/data/constro.data'
+COPY COPY_TBL FROM :'filename';
 
 SELECT * FROM COPY_TBL;
 
-COPY COPY_TBL FROM '@abs_srcdir@/data/constrf.data';
+\set filename :abs_srcdir '/data/constrf.data'
+COPY COPY_TBL FROM :'filename';
 
 SELECT * FROM COPY_TBL;
 
diff --git a/src/test/regress/input/copy.source b/src/test/regress/input/copy.source
index 8acb516801..15e26517ec 100644
--- a/src/test/regress/input/copy.source
+++ b/src/test/regress/input/copy.source
@@ -2,65 +2,90 @@
 -- COPY
 --
 
+-- directory paths are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
+\getenv abs_builddir PG_ABS_BUILDDIR
+
 -- CLASS POPULATION
 --	(any resemblance to real life is purely coincidental)
 --
-COPY aggtest FROM '@abs_srcdir@/data/agg.data';
+\set filename :abs_srcdir '/data/agg.data'
+COPY aggtest FROM :'filename';
 
-COPY onek FROM '@abs_srcdir@/data/onek.data';
+\set filename :abs_srcdir '/data/onek.data'
+COPY onek FROM :'filename';
 
-COPY onek TO '@abs_builddir@/results/onek.data';
+\set filename :abs_builddir '/results/onek.data'
+COPY onek TO :'filename';
 
 DELETE FROM onek;
 
-COPY onek FROM '@abs_builddir@/results/onek.data';
+COPY onek FROM :'filename';
 
-COPY tenk1 FROM '@abs_srcdir@/data/tenk.data';
+\set filename :abs_srcdir '/data/tenk.data'
+COPY tenk1 FROM :'filename';
 
-COPY slow_emp4000 FROM '@abs_srcdir@/data/rect.data';
+\set filename :abs_srcdir '/data/rect.data'
+COPY slow_emp4000 FROM :'filename';
 
-COPY person FROM '@abs_srcdir@/data/person.data';
+\set filename :abs_srcdir '/data/person.data'
+COPY person FROM :'filename';
 
-COPY emp FROM '@abs_srcdir@/data/emp.data';
+\set filename :abs_srcdir '/data/emp.data'
+COPY emp FROM :'filename';
 
-COPY student FROM '@abs_srcdir@/data/student.data';
+\set filename :abs_srcdir '/data/student.data'
+COPY student FROM :'filename';
 
-COPY stud_emp FROM '@abs_srcdir@/data/stud_emp.data';
+\set filename :abs_srcdir '/data/stud_emp.data'
+COPY stud_emp FROM :'filename';
 
-COPY road FROM '@abs_srcdir@/data/streets.data';
+\set filename :abs_srcdir '/data/streets.data'
+COPY road FROM :'filename';
 
-COPY real_city FROM '@abs_srcdir@/data/real_city.data';
+\set filename :abs_srcdir '/data/real_city.data'
+COPY real_city FROM :'filename';
 
-COPY hash_i4_heap FROM '@abs_srcdir@/data/hash.data';
+\set filename :abs_srcdir '/data/hash.data'
+COPY hash_i4_heap FROM :'filename';
 
-COPY hash_name_heap FROM '@abs_srcdir@/data/hash.data';
+COPY hash_name_heap FROM :'filename';
 
-COPY hash_txt_heap FROM '@abs_srcdir@/data/hash.data';
+COPY hash_txt_heap FROM :'filename';
 
-COPY hash_f8_heap FROM '@abs_srcdir@/data/hash.data';
+COPY hash_f8_heap FROM :'filename';
 
-COPY test_tsvector FROM '@abs_srcdir@/data/tsearch.data';
+\set filename :abs_srcdir '/data/tsearch.data'
+COPY test_tsvector FROM :'filename';
 
-COPY testjsonb FROM '@abs_srcdir@/data/jsonb.data';
+\set filename :abs_srcdir '/data/jsonb.data'
+COPY testjsonb FROM :'filename';
 
 -- the data in this file has a lot of duplicates in the index key
 -- fields, leading to long bucket chains and lots of table expansion.
 -- this is therefore a stress test of the bucket overflow code (unlike
 -- the data in hash.data, which has unique index keys).
 --
--- COPY hash_ovfl_heap FROM '@abs_srcdir@/data/hashovfl.data';
+-- \set filename :abs_srcdir '/data/hashovfl.data'
+-- COPY hash_ovfl_heap FROM :'filename';
 
-COPY bt_i4_heap FROM '@abs_srcdir@/data/desc.data';
+\set filename :abs_srcdir '/data/desc.data'
+COPY bt_i4_heap FROM :'filename';
 
-COPY bt_name_heap FROM '@abs_srcdir@/data/hash.data';
+\set filename :abs_srcdir '/data/hash.data'
+COPY bt_name_heap FROM :'filename';
 
-COPY bt_txt_heap FROM '@abs_srcdir@/data/desc.data';
+\set filename :abs_srcdir '/data/desc.data'
+COPY bt_txt_heap FROM :'filename';
 
-COPY bt_f8_heap FROM '@abs_srcdir@/data/hash.data';
+\set filename :abs_srcdir '/data/hash.data'
+COPY bt_f8_heap FROM :'filename';
 
-COPY array_op_test FROM '@abs_srcdir@/data/array.data';
+\set filename :abs_srcdir '/data/array.data'
+COPY array_op_test FROM :'filename';
 
-COPY array_index_op_test FROM '@abs_srcdir@/data/array.data';
+\set filename :abs_srcdir '/data/array.data'
+COPY array_index_op_test FROM :'filename';
 
 -- analyze all the data we just loaded, to ensure plan consistency
 -- in later tests
@@ -100,11 +125,12 @@ insert into copytest values('Unix',E'abc\ndef',2);
 insert into copytest values('Mac',E'abc\rdef',3);
 insert into copytest values(E'esc\\ape',E'a\\r\\\r\\\n\\nb',4);
 
-copy copytest to '@abs_builddir@/results/copytest.csv' csv;
+\set filename :abs_builddir '/results/copytest.csv'
+copy copytest to :'filename' csv;
 
 create temp table copytest2 (like copytest);
 
-copy copytest2 from '@abs_builddir@/results/copytest.csv' csv;
+copy copytest2 from :'filename' csv;
 
 select * from copytest except select * from copytest2;
 
@@ -112,9 +138,9 @@ truncate copytest2;
 
 --- same test but with an escape char different from quote char
 
-copy copytest to '@abs_builddir@/results/copytest.csv' csv quote '''' escape E'\\';
+copy copytest to :'filename' csv quote '''' escape E'\\';
 
-copy copytest2 from '@abs_builddir@/results/copytest.csv' csv quote '''' escape E'\\';
+copy copytest2 from :'filename' csv quote '''' escape E'\\';
 
 select * from copytest except select * from copytest2;
 
@@ -153,16 +179,17 @@ insert into parted_copytest select x,1,'One' from generate_series(1,1000) x;
 insert into parted_copytest select x,2,'Two' from generate_series(1001,1010) x;
 insert into parted_copytest select x,1,'One' from generate_series(1011,1020) x;
 
-copy (select * from parted_copytest order by a) to '@abs_builddir@/results/parted_copytest.csv';
+\set filename :abs_builddir '/results/parted_copytest.csv'
+copy (select * from parted_copytest order by a) to :'filename';
 
 truncate parted_copytest;
 
-copy parted_copytest from '@abs_builddir@/results/parted_copytest.csv';
+copy parted_copytest from :'filename';
 
 -- Ensure COPY FREEZE errors for partitioned tables.
 begin;
 truncate parted_copytest;
-copy parted_copytest from '@abs_builddir@/results/parted_copytest.csv' (freeze);
+copy parted_copytest from :'filename' (freeze);
 rollback;
 
 select tableoid::regclass,count(*),sum(a) from parted_copytest
@@ -182,7 +209,7 @@ create trigger part_ins_trig
 	for each row
 	execute procedure part_ins_func();
 
-copy parted_copytest from '@abs_builddir@/results/parted_copytest.csv';
+copy parted_copytest from :'filename';
 
 select tableoid::regclass,count(*),sum(a) from parted_copytest
 group by tableoid order by tableoid::regclass::name;
@@ -257,7 +284,8 @@ bill	20	(11,10)	1000	sharon
 
 -- Generate COPY FROM report with FILE, with some excluded tuples.
 truncate tab_progress_reporting;
-copy tab_progress_reporting from '@abs_srcdir@/data/emp.data'
+\set filename :abs_srcdir '/data/emp.data'
+copy tab_progress_reporting from :'filename'
 	where (salary < 2000);
 
 drop trigger check_after_tab_progress_reporting on tab_progress_reporting;
diff --git a/src/test/regress/input/create_function_0.source b/src/test/regress/input/create_function_0.source
index f47f635789..c5224742f9 100644
--- a/src/test/regress/input/create_function_0.source
+++ b/src/test/regress/input/create_function_0.source
@@ -2,70 +2,78 @@
 -- CREATE_FUNCTION_0
 --
 
+-- directory path and dlsuffix are passed to us in environment variables
+\getenv libdir PG_LIBDIR
+\getenv dlsuffix PG_DLSUFFIX
+
+\set autoinclib :libdir '/autoinc' :dlsuffix
+\set refintlib :libdir '/refint' :dlsuffix
+\set regresslib :libdir '/regress' :dlsuffix
+
 -- Create a bunch of C functions that will be used by later tests:
 
 CREATE FUNCTION check_primary_key ()
 	RETURNS trigger
-	AS '@libdir@/refint@DLSUFFIX@'
+	AS :'refintlib'
 	LANGUAGE C;
 
 CREATE FUNCTION check_foreign_key ()
 	RETURNS trigger
-	AS '@libdir@/refint@DLSUFFIX@'
+	AS :'refintlib'
 	LANGUAGE C;
 
 CREATE FUNCTION autoinc ()
 	RETURNS trigger
-	AS '@libdir@/autoinc@DLSUFFIX@'
+	AS :'autoinclib'
 	LANGUAGE C;
 
 CREATE FUNCTION trigger_return_old ()
         RETURNS trigger
-        AS '@libdir@/regress@DLSUFFIX@'
+        AS :'regresslib'
         LANGUAGE C;
 
 CREATE FUNCTION ttdummy ()
         RETURNS trigger
-        AS '@libdir@/regress@DLSUFFIX@'
+        AS :'regresslib'
         LANGUAGE C;
 
 CREATE FUNCTION set_ttdummy (int4)
         RETURNS int4
-        AS '@libdir@/regress@DLSUFFIX@'
+        AS :'regresslib'
         LANGUAGE C STRICT;
 
 CREATE FUNCTION make_tuple_indirect (record)
         RETURNS record
-        AS '@libdir@/regress@DLSUFFIX@'
+        AS :'regresslib'
         LANGUAGE C STRICT;
 
 CREATE FUNCTION test_atomic_ops()
     RETURNS bool
-    AS '@libdir@/regress@DLSUFFIX@'
+    AS :'regresslib'
     LANGUAGE C;
 
 CREATE FUNCTION test_fdw_handler()
     RETURNS fdw_handler
-    AS '@libdir@/regress@DLSUFFIX@', 'test_fdw_handler'
+    AS :'regresslib', 'test_fdw_handler'
     LANGUAGE C;
 
 CREATE FUNCTION test_support_func(internal)
     RETURNS internal
-    AS '@libdir@/regress@DLSUFFIX@', 'test_support_func'
+    AS :'regresslib', 'test_support_func'
     LANGUAGE C STRICT;
 
 CREATE FUNCTION test_opclass_options_func(internal)
     RETURNS void
-    AS '@libdir@/regress@DLSUFFIX@', 'test_opclass_options_func'
+    AS :'regresslib', 'test_opclass_options_func'
     LANGUAGE C;
 
 CREATE FUNCTION test_enc_conversion(bytea, name, name, bool, validlen OUT int, result OUT bytea)
-    AS '@libdir@/regress@DLSUFFIX@', 'test_enc_conversion'
+    AS :'regresslib', 'test_enc_conversion'
     LANGUAGE C STRICT;
 
 CREATE FUNCTION binary_coercible(oid, oid)
     RETURNS bool
-    AS '@libdir@/regress@DLSUFFIX@', 'binary_coercible'
+    AS :'regresslib', 'binary_coercible'
     LANGUAGE C STRICT STABLE PARALLEL SAFE;
 
 -- Things that shouldn't work:
@@ -88,8 +96,13 @@ CREATE FUNCTION test1 (int) RETURNS int LANGUAGE SQL
 CREATE FUNCTION test1 (int) RETURNS int LANGUAGE C
     AS 'nosuchfile';
 
+-- To produce stable regression test output, we have to filter the name
+-- of the regresslib file out of the error message in this test.
+\set VERBOSITY sqlstate
 CREATE FUNCTION test1 (int) RETURNS int LANGUAGE C
-    AS '@libdir@/regress@DLSUFFIX@', 'nosuchsymbol';
+    AS :'regresslib', 'nosuchsymbol';
+\set VERBOSITY default
+SELECT regexp_replace(:'LAST_ERROR_MESSAGE', 'file ".*"', 'file "..."');
 
 CREATE FUNCTION test1 (int) RETURNS int LANGUAGE internal
     AS 'nosuch';
diff --git a/src/test/regress/input/create_function_1.source b/src/test/regress/input/create_function_1.source
index 79a41562bb..4170b16fe6 100644
--- a/src/test/regress/input/create_function_1.source
+++ b/src/test/regress/input/create_function_1.source
@@ -2,24 +2,30 @@
 -- CREATE_FUNCTION_1
 --
 
+-- directory path and dlsuffix are passed to us in environment variables
+\getenv libdir PG_LIBDIR
+\getenv dlsuffix PG_DLSUFFIX
+
+\set regresslib :libdir '/regress' :dlsuffix
+
 -- Create C functions needed by create_type.sql
 
 CREATE FUNCTION widget_in(cstring)
    RETURNS widget
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT IMMUTABLE;
 
 CREATE FUNCTION widget_out(widget)
    RETURNS cstring
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT IMMUTABLE;
 
 CREATE FUNCTION int44in(cstring)
    RETURNS city_budget
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT IMMUTABLE;
 
 CREATE FUNCTION int44out(city_budget)
    RETURNS cstring
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT IMMUTABLE;
diff --git a/src/test/regress/input/create_function_2.source b/src/test/regress/input/create_function_2.source
index 9e6d2942ec..67510aed23 100644
--- a/src/test/regress/input/create_function_2.source
+++ b/src/test/regress/input/create_function_2.source
@@ -1,6 +1,14 @@
 --
 -- CREATE_FUNCTION_2
 --
+
+-- directory path and dlsuffix are passed to us in environment variables
+\getenv libdir PG_LIBDIR
+\getenv dlsuffix PG_DLSUFFIX
+
+\set regresslib :libdir '/regress' :dlsuffix
+
+
 CREATE FUNCTION hobbies(person)
    RETURNS setof hobbies_r
    AS 'select * from hobbies_r where person = $1.name'
@@ -64,25 +72,25 @@ CREATE FUNCTION equipment_named_ambiguous_2b(hobby text)
 
 CREATE FUNCTION pt_in_widget(point, widget)
    RETURNS bool
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT;
 
 CREATE FUNCTION overpaid(emp)
    RETURNS bool
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT;
 
 CREATE FUNCTION interpt_pp(path, path)
    RETURNS point
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT;
 
 CREATE FUNCTION reverse_name(name)
    RETURNS name
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT;
 
 --
 -- Function dynamic loading
 --
-LOAD '@libdir@/regress@DLSUFFIX@';
+LOAD :'regresslib';
diff --git a/src/test/regress/input/largeobject.source b/src/test/regress/input/largeobject.source
index b1e7ae9909..16da077f3a 100644
--- a/src/test/regress/input/largeobject.source
+++ b/src/test/regress/input/largeobject.source
@@ -2,6 +2,10 @@
 -- Test large object support
 --
 
+-- directory paths are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
+\getenv abs_builddir PG_ABS_BUILDDIR
+
 -- ensure consistent test output regardless of the default bytea format
 SET bytea_output TO escape;
 
@@ -124,16 +128,13 @@ BEGIN;
 SELECT lo_open(loid, x'40000'::int) from lotest_stash_values;
 ABORT;
 
-DO $$
-DECLARE
-  loid oid;
-BEGIN
-  SELECT tbl.loid INTO loid FROM lotest_stash_values tbl;
-  PERFORM lo_export(loid, '@abs_builddir@/results/invalid/path');
-EXCEPTION
-  WHEN UNDEFINED_FILE THEN RAISE NOTICE 'could not open file, as expected';
-END;
-$$;
+\set filename :abs_builddir '/results/invalid/path'
+\set dobody 'DECLARE loid oid; BEGIN '
+\set dobody :dobody 'SELECT tbl.loid INTO loid FROM lotest_stash_values tbl; '
+\set dobody :dobody 'PERFORM lo_export(loid, ' :'filename' '); '
+\set dobody :dobody 'EXCEPTION WHEN UNDEFINED_FILE THEN '
+\set dobody :dobody 'RAISE NOTICE ''could not open file, as expected''; END'
+DO :'dobody';
 
 -- Test truncation.
 BEGIN;
@@ -183,7 +184,8 @@ SELECT lo_unlink(loid) from lotest_stash_values;
 
 TRUNCATE lotest_stash_values;
 
-INSERT INTO lotest_stash_values (loid) SELECT lo_import('@abs_srcdir@/data/tenk.data');
+\set filename :abs_srcdir '/data/tenk.data'
+INSERT INTO lotest_stash_values (loid) SELECT lo_import(:'filename');
 
 BEGIN;
 UPDATE lotest_stash_values SET fd=lo_open(loid, CAST(x'20000' | x'40000' AS integer));
@@ -212,14 +214,16 @@ SELECT loread(fd, 36) FROM lotest_stash_values;
 SELECT lo_close(fd) FROM lotest_stash_values;
 END;
 
-SELECT lo_export(loid, '@abs_builddir@/results/lotest.txt') FROM lotest_stash_values;
+\set filename :abs_builddir '/results/lotest.txt'
+SELECT lo_export(loid, :'filename') FROM lotest_stash_values;
 
-\lo_import '@abs_builddir@/results/lotest.txt'
+\lo_import :filename
 
 \set newloid :LASTOID
 
 -- just make sure \lo_export does not barf
-\lo_export :newloid '@abs_builddir@/results/lotest2.txt'
+\set filename :abs_builddir '/results/lotest2.txt'
+\lo_export :newloid :filename
 
 -- This is a hack to test that export/import are reversible
 -- This uses knowledge about the inner workings of large object mechanism
@@ -234,7 +238,8 @@ TRUNCATE lotest_stash_values;
 
 \lo_unlink :newloid
 
-\lo_import '@abs_builddir@/results/lotest.txt'
+\set filename :abs_builddir '/results/lotest.txt'
+\lo_import :filename
 
 \set newloid_1 :LASTOID
 
diff --git a/src/test/regress/input/misc.source b/src/test/regress/input/misc.source
index b1dbc573c9..a1e2f779ba 100644
--- a/src/test/regress/input/misc.source
+++ b/src/test/regress/input/misc.source
@@ -2,6 +2,10 @@
 -- MISC
 --
 
+-- directory paths are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
+\getenv abs_builddir PG_ABS_BUILDDIR
+
 --
 -- BTREE
 --
@@ -51,25 +55,27 @@ DROP TABLE tmp;
 --
 -- copy
 --
-COPY onek TO '@abs_builddir@/results/onek.data';
+\set filename :abs_builddir '/results/onek.data'
+COPY onek TO :'filename';
 
 DELETE FROM onek;
 
-COPY onek FROM '@abs_builddir@/results/onek.data';
+COPY onek FROM :'filename';
 
 SELECT unique1 FROM onek WHERE unique1 < 2 ORDER BY unique1;
 
 DELETE FROM onek2;
 
-COPY onek2 FROM '@abs_builddir@/results/onek.data';
+COPY onek2 FROM :'filename';
 
 SELECT unique1 FROM onek2 WHERE unique1 < 2 ORDER BY unique1;
 
-COPY BINARY stud_emp TO '@abs_builddir@/results/stud_emp.data';
+\set filename :abs_builddir '/results/stud_emp.data'
+COPY BINARY stud_emp TO :'filename';
 
 DELETE FROM stud_emp;
 
-COPY BINARY stud_emp FROM '@abs_builddir@/results/stud_emp.data';
+COPY BINARY stud_emp FROM :'filename';
 
 SELECT * FROM stud_emp;
 
diff --git a/src/test/regress/input/tablespace.source b/src/test/regress/input/tablespace.source
index c133e73499..92076db9a1 100644
--- a/src/test/regress/input/tablespace.source
+++ b/src/test/regress/input/tablespace.source
@@ -1,6 +1,11 @@
+-- directory paths are passed to us in environment variables
+\getenv abs_builddir PG_ABS_BUILDDIR
+
+\set testtablespace :abs_builddir '/testtablespace'
+
 -- create a tablespace using WITH clause
-CREATE TABLESPACE regress_tblspacewith LOCATION '@testtablespace@' WITH (some_nonexistent_parameter = true); -- fail
-CREATE TABLESPACE regress_tblspacewith LOCATION '@testtablespace@' WITH (random_page_cost = 3.0); -- ok
+CREATE TABLESPACE regress_tblspacewith LOCATION :'testtablespace' WITH (some_nonexistent_parameter = true); -- fail
+CREATE TABLESPACE regress_tblspacewith LOCATION :'testtablespace' WITH (random_page_cost = 3.0); -- ok
 
 -- check to see the parameter was used
 SELECT spcoptions FROM pg_tablespace WHERE spcname = 'regress_tblspacewith';
@@ -9,7 +14,7 @@ SELECT spcoptions FROM pg_tablespace WHERE spcname = 'regress_tblspacewith';
 DROP TABLESPACE regress_tblspacewith;
 
 -- create a tablespace we can use
-CREATE TABLESPACE regress_tblspace LOCATION '@testtablespace@';
+CREATE TABLESPACE regress_tblspace LOCATION :'testtablespace';
 
 -- try setting and resetting some properties for the new tablespace
 ALTER TABLESPACE regress_tblspace SET (random_page_cost = 1.0, seq_page_cost = 1.1);
diff --git a/src/test/regress/output/constraints.source b/src/test/regress/output/constraints.source
index eff793cc3d..e32cf8bb57 100644
--- a/src/test/regress/output/constraints.source
+++ b/src/test/regress/output/constraints.source
@@ -7,6 +7,8 @@
 --  - UNIQUE clauses
 --  - EXCLUDE clauses
 --
+-- directory paths are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
 --
 -- DEFAULT syntax
 --
@@ -346,7 +348,8 @@ SELECT * FROM INSERT_TBL;
 CREATE TABLE COPY_TBL (x INT, y TEXT, z INT,
 	CONSTRAINT COPY_CON
 	CHECK (x > 3 AND y <> 'check failed' AND x < 7 ));
-COPY COPY_TBL FROM '@abs_srcdir@/data/constro.data';
+\set filename :abs_srcdir '/data/constro.data'
+COPY COPY_TBL FROM :'filename';
 SELECT * FROM COPY_TBL;
  x |       y       | z 
 ---+---------------+---
@@ -354,7 +357,8 @@ SELECT * FROM COPY_TBL;
  6 | OK            | 4
 (2 rows)
 
-COPY COPY_TBL FROM '@abs_srcdir@/data/constrf.data';
+\set filename :abs_srcdir '/data/constrf.data'
+COPY COPY_TBL FROM :'filename';
 ERROR:  new row for relation "copy_tbl" violates check constraint "copy_con"
 DETAIL:  Failing row contains (7, check failed, 6).
 CONTEXT:  COPY copy_tbl, line 2: "7	check failed	6"
diff --git a/src/test/regress/output/copy.source b/src/test/regress/output/copy.source
index 25bdec6c60..931e7b2e69 100644
--- a/src/test/regress/output/copy.source
+++ b/src/test/regress/output/copy.source
@@ -1,40 +1,64 @@
 --
 -- COPY
 --
+-- directory paths are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
+\getenv abs_builddir PG_ABS_BUILDDIR
 -- CLASS POPULATION
 --	(any resemblance to real life is purely coincidental)
 --
-COPY aggtest FROM '@abs_srcdir@/data/agg.data';
-COPY onek FROM '@abs_srcdir@/data/onek.data';
-COPY onek TO '@abs_builddir@/results/onek.data';
+\set filename :abs_srcdir '/data/agg.data'
+COPY aggtest FROM :'filename';
+\set filename :abs_srcdir '/data/onek.data'
+COPY onek FROM :'filename';
+\set filename :abs_builddir '/results/onek.data'
+COPY onek TO :'filename';
 DELETE FROM onek;
-COPY onek FROM '@abs_builddir@/results/onek.data';
-COPY tenk1 FROM '@abs_srcdir@/data/tenk.data';
-COPY slow_emp4000 FROM '@abs_srcdir@/data/rect.data';
-COPY person FROM '@abs_srcdir@/data/person.data';
-COPY emp FROM '@abs_srcdir@/data/emp.data';
-COPY student FROM '@abs_srcdir@/data/student.data';
-COPY stud_emp FROM '@abs_srcdir@/data/stud_emp.data';
-COPY road FROM '@abs_srcdir@/data/streets.data';
-COPY real_city FROM '@abs_srcdir@/data/real_city.data';
-COPY hash_i4_heap FROM '@abs_srcdir@/data/hash.data';
-COPY hash_name_heap FROM '@abs_srcdir@/data/hash.data';
-COPY hash_txt_heap FROM '@abs_srcdir@/data/hash.data';
-COPY hash_f8_heap FROM '@abs_srcdir@/data/hash.data';
-COPY test_tsvector FROM '@abs_srcdir@/data/tsearch.data';
-COPY testjsonb FROM '@abs_srcdir@/data/jsonb.data';
+COPY onek FROM :'filename';
+\set filename :abs_srcdir '/data/tenk.data'
+COPY tenk1 FROM :'filename';
+\set filename :abs_srcdir '/data/rect.data'
+COPY slow_emp4000 FROM :'filename';
+\set filename :abs_srcdir '/data/person.data'
+COPY person FROM :'filename';
+\set filename :abs_srcdir '/data/emp.data'
+COPY emp FROM :'filename';
+\set filename :abs_srcdir '/data/student.data'
+COPY student FROM :'filename';
+\set filename :abs_srcdir '/data/stud_emp.data'
+COPY stud_emp FROM :'filename';
+\set filename :abs_srcdir '/data/streets.data'
+COPY road FROM :'filename';
+\set filename :abs_srcdir '/data/real_city.data'
+COPY real_city FROM :'filename';
+\set filename :abs_srcdir '/data/hash.data'
+COPY hash_i4_heap FROM :'filename';
+COPY hash_name_heap FROM :'filename';
+COPY hash_txt_heap FROM :'filename';
+COPY hash_f8_heap FROM :'filename';
+\set filename :abs_srcdir '/data/tsearch.data'
+COPY test_tsvector FROM :'filename';
+\set filename :abs_srcdir '/data/jsonb.data'
+COPY testjsonb FROM :'filename';
 -- the data in this file has a lot of duplicates in the index key
 -- fields, leading to long bucket chains and lots of table expansion.
 -- this is therefore a stress test of the bucket overflow code (unlike
 -- the data in hash.data, which has unique index keys).
 --
--- COPY hash_ovfl_heap FROM '@abs_srcdir@/data/hashovfl.data';
-COPY bt_i4_heap FROM '@abs_srcdir@/data/desc.data';
-COPY bt_name_heap FROM '@abs_srcdir@/data/hash.data';
-COPY bt_txt_heap FROM '@abs_srcdir@/data/desc.data';
-COPY bt_f8_heap FROM '@abs_srcdir@/data/hash.data';
-COPY array_op_test FROM '@abs_srcdir@/data/array.data';
-COPY array_index_op_test FROM '@abs_srcdir@/data/array.data';
+-- \set filename :abs_srcdir '/data/hashovfl.data'
+-- COPY hash_ovfl_heap FROM :'filename';
+\set filename :abs_srcdir '/data/desc.data'
+COPY bt_i4_heap FROM :'filename';
+\set filename :abs_srcdir '/data/hash.data'
+COPY bt_name_heap FROM :'filename';
+\set filename :abs_srcdir '/data/desc.data'
+COPY bt_txt_heap FROM :'filename';
+\set filename :abs_srcdir '/data/hash.data'
+COPY bt_f8_heap FROM :'filename';
+\set filename :abs_srcdir '/data/array.data'
+COPY array_op_test FROM :'filename';
+\set filename :abs_srcdir '/data/array.data'
+COPY array_index_op_test FROM :'filename';
 -- analyze all the data we just loaded, to ensure plan consistency
 -- in later tests
 ANALYZE aggtest;
@@ -68,9 +92,10 @@ insert into copytest values('DOS',E'abc\r\ndef',1);
 insert into copytest values('Unix',E'abc\ndef',2);
 insert into copytest values('Mac',E'abc\rdef',3);
 insert into copytest values(E'esc\\ape',E'a\\r\\\r\\\n\\nb',4);
-copy copytest to '@abs_builddir@/results/copytest.csv' csv;
+\set filename :abs_builddir '/results/copytest.csv'
+copy copytest to :'filename' csv;
 create temp table copytest2 (like copytest);
-copy copytest2 from '@abs_builddir@/results/copytest.csv' csv;
+copy copytest2 from :'filename' csv;
 select * from copytest except select * from copytest2;
  style | test | filler 
 -------+------+--------
@@ -78,8 +103,8 @@ select * from copytest except select * from copytest2;
 
 truncate copytest2;
 --- same test but with an escape char different from quote char
-copy copytest to '@abs_builddir@/results/copytest.csv' csv quote '''' escape E'\\';
-copy copytest2 from '@abs_builddir@/results/copytest.csv' csv quote '''' escape E'\\';
+copy copytest to :'filename' csv quote '''' escape E'\\';
+copy copytest2 from :'filename' csv quote '''' escape E'\\';
 select * from copytest except select * from copytest2;
  style | test | filler 
 -------+------+--------
@@ -110,13 +135,14 @@ alter table parted_copytest attach partition parted_copytest_a2 for values in(2)
 insert into parted_copytest select x,1,'One' from generate_series(1,1000) x;
 insert into parted_copytest select x,2,'Two' from generate_series(1001,1010) x;
 insert into parted_copytest select x,1,'One' from generate_series(1011,1020) x;
-copy (select * from parted_copytest order by a) to '@abs_builddir@/results/parted_copytest.csv';
+\set filename :abs_builddir '/results/parted_copytest.csv'
+copy (select * from parted_copytest order by a) to :'filename';
 truncate parted_copytest;
-copy parted_copytest from '@abs_builddir@/results/parted_copytest.csv';
+copy parted_copytest from :'filename';
 -- Ensure COPY FREEZE errors for partitioned tables.
 begin;
 truncate parted_copytest;
-copy parted_copytest from '@abs_builddir@/results/parted_copytest.csv' (freeze);
+copy parted_copytest from :'filename' (freeze);
 ERROR:  cannot perform COPY FREEZE on a partitioned table
 rollback;
 select tableoid::regclass,count(*),sum(a) from parted_copytest
@@ -138,7 +164,7 @@ create trigger part_ins_trig
 	before insert on parted_copytest_a2
 	for each row
 	execute procedure part_ins_func();
-copy parted_copytest from '@abs_builddir@/results/parted_copytest.csv';
+copy parted_copytest from :'filename';
 select tableoid::regclass,count(*),sum(a) from parted_copytest
 group by tableoid order by tableoid::regclass::name;
       tableoid      | count |  sum   
@@ -213,7 +239,8 @@ copy tab_progress_reporting from stdin;
 INFO:  progress: {"type": "PIPE", "command": "COPY FROM", "relname": "tab_progress_reporting", "has_bytes_total": false, "tuples_excluded": 0, "tuples_processed": 3, "has_bytes_processed": true}
 -- Generate COPY FROM report with FILE, with some excluded tuples.
 truncate tab_progress_reporting;
-copy tab_progress_reporting from '@abs_srcdir@/data/emp.data'
+\set filename :abs_srcdir '/data/emp.data'
+copy tab_progress_reporting from :'filename'
 	where (salary < 2000);
 INFO:  progress: {"type": "FILE", "command": "COPY FROM", "relname": "tab_progress_reporting", "has_bytes_total": true, "tuples_excluded": 1, "tuples_processed": 2, "has_bytes_processed": true}
 drop trigger check_after_tab_progress_reporting on tab_progress_reporting;
diff --git a/src/test/regress/output/create_function_0.source b/src/test/regress/output/create_function_0.source
index 342bc40e11..6e96d6c5d6 100644
--- a/src/test/regress/output/create_function_0.source
+++ b/src/test/regress/output/create_function_0.source
@@ -1,57 +1,63 @@
 --
 -- CREATE_FUNCTION_0
 --
+-- directory path and dlsuffix are passed to us in environment variables
+\getenv libdir PG_LIBDIR
+\getenv dlsuffix PG_DLSUFFIX
+\set autoinclib :libdir '/autoinc' :dlsuffix
+\set refintlib :libdir '/refint' :dlsuffix
+\set regresslib :libdir '/regress' :dlsuffix
 -- Create a bunch of C functions that will be used by later tests:
 CREATE FUNCTION check_primary_key ()
 	RETURNS trigger
-	AS '@libdir@/refint@DLSUFFIX@'
+	AS :'refintlib'
 	LANGUAGE C;
 CREATE FUNCTION check_foreign_key ()
 	RETURNS trigger
-	AS '@libdir@/refint@DLSUFFIX@'
+	AS :'refintlib'
 	LANGUAGE C;
 CREATE FUNCTION autoinc ()
 	RETURNS trigger
-	AS '@libdir@/autoinc@DLSUFFIX@'
+	AS :'autoinclib'
 	LANGUAGE C;
 CREATE FUNCTION trigger_return_old ()
         RETURNS trigger
-        AS '@libdir@/regress@DLSUFFIX@'
+        AS :'regresslib'
         LANGUAGE C;
 CREATE FUNCTION ttdummy ()
         RETURNS trigger
-        AS '@libdir@/regress@DLSUFFIX@'
+        AS :'regresslib'
         LANGUAGE C;
 CREATE FUNCTION set_ttdummy (int4)
         RETURNS int4
-        AS '@libdir@/regress@DLSUFFIX@'
+        AS :'regresslib'
         LANGUAGE C STRICT;
 CREATE FUNCTION make_tuple_indirect (record)
         RETURNS record
-        AS '@libdir@/regress@DLSUFFIX@'
+        AS :'regresslib'
         LANGUAGE C STRICT;
 CREATE FUNCTION test_atomic_ops()
     RETURNS bool
-    AS '@libdir@/regress@DLSUFFIX@'
+    AS :'regresslib'
     LANGUAGE C;
 CREATE FUNCTION test_fdw_handler()
     RETURNS fdw_handler
-    AS '@libdir@/regress@DLSUFFIX@', 'test_fdw_handler'
+    AS :'regresslib', 'test_fdw_handler'
     LANGUAGE C;
 CREATE FUNCTION test_support_func(internal)
     RETURNS internal
-    AS '@libdir@/regress@DLSUFFIX@', 'test_support_func'
+    AS :'regresslib', 'test_support_func'
     LANGUAGE C STRICT;
 CREATE FUNCTION test_opclass_options_func(internal)
     RETURNS void
-    AS '@libdir@/regress@DLSUFFIX@', 'test_opclass_options_func'
+    AS :'regresslib', 'test_opclass_options_func'
     LANGUAGE C;
 CREATE FUNCTION test_enc_conversion(bytea, name, name, bool, validlen OUT int, result OUT bytea)
-    AS '@libdir@/regress@DLSUFFIX@', 'test_enc_conversion'
+    AS :'regresslib', 'test_enc_conversion'
     LANGUAGE C STRICT;
 CREATE FUNCTION binary_coercible(oid, oid)
     RETURNS bool
-    AS '@libdir@/regress@DLSUFFIX@', 'binary_coercible'
+    AS :'regresslib', 'binary_coercible'
     LANGUAGE C STRICT STABLE PARALLEL SAFE;
 -- Things that shouldn't work:
 CREATE FUNCTION test1 (int) RETURNS int LANGUAGE SQL
@@ -80,9 +86,19 @@ ERROR:  only one AS item needed for language "sql"
 CREATE FUNCTION test1 (int) RETURNS int LANGUAGE C
     AS 'nosuchfile';
 ERROR:  could not access file "nosuchfile": No such file or directory
+-- To produce stable regression test output, we have to filter the name
+-- of the regresslib file out of the error message in this test.
+\set VERBOSITY sqlstate
 CREATE FUNCTION test1 (int) RETURNS int LANGUAGE C
-    AS '@libdir@/regress@DLSUFFIX@', 'nosuchsymbol';
-ERROR:  could not find function "nosuchsymbol" in file "@libdir@/regress@DLSUFFIX@"
+    AS :'regresslib', 'nosuchsymbol';
+ERROR:  42883
+\set VERBOSITY default
+SELECT regexp_replace(:'LAST_ERROR_MESSAGE', 'file ".*"', 'file "..."');
+                    regexp_replace                    
+------------------------------------------------------
+ could not find function "nosuchsymbol" in file "..."
+(1 row)
+
 CREATE FUNCTION test1 (int) RETURNS int LANGUAGE internal
     AS 'nosuch';
 ERROR:  there is no built-in function named "nosuch"
diff --git a/src/test/regress/output/create_function_1.source b/src/test/regress/output/create_function_1.source
index 616b610e86..5345ed0840 100644
--- a/src/test/regress/output/create_function_1.source
+++ b/src/test/regress/output/create_function_1.source
@@ -1,26 +1,30 @@
 --
 -- CREATE_FUNCTION_1
 --
+-- directory path and dlsuffix are passed to us in environment variables
+\getenv libdir PG_LIBDIR
+\getenv dlsuffix PG_DLSUFFIX
+\set regresslib :libdir '/regress' :dlsuffix
 -- Create C functions needed by create_type.sql
 CREATE FUNCTION widget_in(cstring)
    RETURNS widget
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT IMMUTABLE;
 NOTICE:  type "widget" is not yet defined
 DETAIL:  Creating a shell type definition.
 CREATE FUNCTION widget_out(widget)
    RETURNS cstring
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT IMMUTABLE;
 NOTICE:  argument type widget is only a shell
 CREATE FUNCTION int44in(cstring)
    RETURNS city_budget
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT IMMUTABLE;
 NOTICE:  type "city_budget" is not yet defined
 DETAIL:  Creating a shell type definition.
 CREATE FUNCTION int44out(city_budget)
    RETURNS cstring
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT IMMUTABLE;
 NOTICE:  argument type city_budget is only a shell
diff --git a/src/test/regress/output/create_function_2.source b/src/test/regress/output/create_function_2.source
index ac9a7f5cf8..a366294add 100644
--- a/src/test/regress/output/create_function_2.source
+++ b/src/test/regress/output/create_function_2.source
@@ -1,6 +1,10 @@
 --
 -- CREATE_FUNCTION_2
 --
+-- directory path and dlsuffix are passed to us in environment variables
+\getenv libdir PG_LIBDIR
+\getenv dlsuffix PG_DLSUFFIX
+\set regresslib :libdir '/regress' :dlsuffix
 CREATE FUNCTION hobbies(person)
    RETURNS setof hobbies_r
    AS 'select * from hobbies_r where person = $1.name'
@@ -49,21 +53,21 @@ CREATE FUNCTION equipment_named_ambiguous_2b(hobby text)
    LANGUAGE SQL;
 CREATE FUNCTION pt_in_widget(point, widget)
    RETURNS bool
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT;
 CREATE FUNCTION overpaid(emp)
    RETURNS bool
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT;
 CREATE FUNCTION interpt_pp(path, path)
    RETURNS point
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT;
 CREATE FUNCTION reverse_name(name)
    RETURNS name
-   AS '@libdir@/regress@DLSUFFIX@'
+   AS :'regresslib'
    LANGUAGE C STRICT;
 --
 -- Function dynamic loading
 --
-LOAD '@libdir@/regress@DLSUFFIX@';
+LOAD :'regresslib';
diff --git a/src/test/regress/output/largeobject.source b/src/test/regress/output/largeobject.source
index 91d33b4d0c..f461ca3b9f 100644
--- a/src/test/regress/output/largeobject.source
+++ b/src/test/regress/output/largeobject.source
@@ -1,6 +1,9 @@
 --
 -- Test large object support
 --
+-- directory paths are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
+\getenv abs_builddir PG_ABS_BUILDDIR
 -- ensure consistent test output regardless of the default bytea format
 SET bytea_output TO escape;
 -- Load a file
@@ -161,16 +164,13 @@ SELECT lo_open(loid, x'40000'::int) from lotest_stash_values;
 (1 row)
 
 ABORT;
-DO $$
-DECLARE
-  loid oid;
-BEGIN
-  SELECT tbl.loid INTO loid FROM lotest_stash_values tbl;
-  PERFORM lo_export(loid, '@abs_builddir@/results/invalid/path');
-EXCEPTION
-  WHEN UNDEFINED_FILE THEN RAISE NOTICE 'could not open file, as expected';
-END;
-$$;
+\set filename :abs_builddir '/results/invalid/path'
+\set dobody 'DECLARE loid oid; BEGIN '
+\set dobody :dobody 'SELECT tbl.loid INTO loid FROM lotest_stash_values tbl; '
+\set dobody :dobody 'PERFORM lo_export(loid, ' :'filename' '); '
+\set dobody :dobody 'EXCEPTION WHEN UNDEFINED_FILE THEN '
+\set dobody :dobody 'RAISE NOTICE ''could not open file, as expected''; END'
+DO :'dobody';
 NOTICE:  could not open file, as expected
 -- Test truncation.
 BEGIN;
@@ -327,7 +327,8 @@ SELECT lo_unlink(loid) from lotest_stash_values;
 (1 row)
 
 TRUNCATE lotest_stash_values;
-INSERT INTO lotest_stash_values (loid) SELECT lo_import('@abs_srcdir@/data/tenk.data');
+\set filename :abs_srcdir '/data/tenk.data'
+INSERT INTO lotest_stash_values (loid) SELECT lo_import(:'filename');
 BEGIN;
 UPDATE lotest_stash_values SET fd=lo_open(loid, CAST(x'20000' | x'40000' AS integer));
 -- verify length of large object
@@ -390,16 +391,18 @@ SELECT lo_close(fd) FROM lotest_stash_values;
 (1 row)
 
 END;
-SELECT lo_export(loid, '@abs_builddir@/results/lotest.txt') FROM lotest_stash_values;
+\set filename :abs_builddir '/results/lotest.txt'
+SELECT lo_export(loid, :'filename') FROM lotest_stash_values;
  lo_export 
 -----------
          1
 (1 row)
 
-\lo_import '@abs_builddir@/results/lotest.txt'
+\lo_import :filename
 \set newloid :LASTOID
 -- just make sure \lo_export does not barf
-\lo_export :newloid '@abs_builddir@/results/lotest2.txt'
+\set filename :abs_builddir '/results/lotest2.txt'
+\lo_export :newloid :filename
 -- This is a hack to test that export/import are reversible
 -- This uses knowledge about the inner workings of large object mechanism
 -- which should not be used outside it.  This makes it a HACK
@@ -418,7 +421,8 @@ SELECT lo_unlink(loid) FROM lotest_stash_values;
 
 TRUNCATE lotest_stash_values;
 \lo_unlink :newloid
-\lo_import '@abs_builddir@/results/lotest.txt'
+\set filename :abs_builddir '/results/lotest.txt'
+\lo_import :filename
 \set newloid_1 :LASTOID
 SELECT lo_from_bytea(0, lo_get(:newloid_1)) AS newloid_2
 \gset
diff --git a/src/test/regress/output/largeobject_1.source b/src/test/regress/output/largeobject_1.source
index cb910e2eef..a9725c375d 100644
--- a/src/test/regress/output/largeobject_1.source
+++ b/src/test/regress/output/largeobject_1.source
@@ -1,6 +1,9 @@
 --
 -- Test large object support
 --
+-- directory paths are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
+\getenv abs_builddir PG_ABS_BUILDDIR
 -- ensure consistent test output regardless of the default bytea format
 SET bytea_output TO escape;
 -- Load a file
@@ -161,16 +164,13 @@ SELECT lo_open(loid, x'40000'::int) from lotest_stash_values;
 (1 row)
 
 ABORT;
-DO $$
-DECLARE
-  loid oid;
-BEGIN
-  SELECT tbl.loid INTO loid FROM lotest_stash_values tbl;
-  PERFORM lo_export(loid, '@abs_builddir@/results/invalid/path');
-EXCEPTION
-  WHEN UNDEFINED_FILE THEN RAISE NOTICE 'could not open file, as expected';
-END;
-$$;
+\set filename :abs_builddir '/results/invalid/path'
+\set dobody 'DECLARE loid oid; BEGIN '
+\set dobody :dobody 'SELECT tbl.loid INTO loid FROM lotest_stash_values tbl; '
+\set dobody :dobody 'PERFORM lo_export(loid, ' :'filename' '); '
+\set dobody :dobody 'EXCEPTION WHEN UNDEFINED_FILE THEN '
+\set dobody :dobody 'RAISE NOTICE ''could not open file, as expected''; END'
+DO :'dobody';
 NOTICE:  could not open file, as expected
 -- Test truncation.
 BEGIN;
@@ -327,7 +327,8 @@ SELECT lo_unlink(loid) from lotest_stash_values;
 (1 row)
 
 TRUNCATE lotest_stash_values;
-INSERT INTO lotest_stash_values (loid) SELECT lo_import('@abs_srcdir@/data/tenk.data');
+\set filename :abs_srcdir '/data/tenk.data'
+INSERT INTO lotest_stash_values (loid) SELECT lo_import(:'filename');
 BEGIN;
 UPDATE lotest_stash_values SET fd=lo_open(loid, CAST(x'20000' | x'40000' AS integer));
 -- verify length of large object
@@ -390,16 +391,18 @@ SELECT lo_close(fd) FROM lotest_stash_values;
 (1 row)
 
 END;
-SELECT lo_export(loid, '@abs_builddir@/results/lotest.txt') FROM lotest_stash_values;
+\set filename :abs_builddir '/results/lotest.txt'
+SELECT lo_export(loid, :'filename') FROM lotest_stash_values;
  lo_export 
 -----------
          1
 (1 row)
 
-\lo_import '@abs_builddir@/results/lotest.txt'
+\lo_import :filename
 \set newloid :LASTOID
 -- just make sure \lo_export does not barf
-\lo_export :newloid '@abs_builddir@/results/lotest2.txt'
+\set filename :abs_builddir '/results/lotest2.txt'
+\lo_export :newloid :filename
 -- This is a hack to test that export/import are reversible
 -- This uses knowledge about the inner workings of large object mechanism
 -- which should not be used outside it.  This makes it a HACK
@@ -418,7 +421,8 @@ SELECT lo_unlink(loid) FROM lotest_stash_values;
 
 TRUNCATE lotest_stash_values;
 \lo_unlink :newloid
-\lo_import '@abs_builddir@/results/lotest.txt'
+\set filename :abs_builddir '/results/lotest.txt'
+\lo_import :filename
 \set newloid_1 :LASTOID
 SELECT lo_from_bytea(0, lo_get(:newloid_1)) AS newloid_2
 \gset
diff --git a/src/test/regress/output/misc.source b/src/test/regress/output/misc.source
index b9595cc239..dd65e6ed62 100644
--- a/src/test/regress/output/misc.source
+++ b/src/test/regress/output/misc.source
@@ -1,6 +1,9 @@
 --
 -- MISC
 --
+-- directory paths are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
+\getenv abs_builddir PG_ABS_BUILDDIR
 --
 -- BTREE
 --
@@ -41,9 +44,10 @@ DROP TABLE tmp;
 --
 -- copy
 --
-COPY onek TO '@abs_builddir@/results/onek.data';
+\set filename :abs_builddir '/results/onek.data'
+COPY onek TO :'filename';
 DELETE FROM onek;
-COPY onek FROM '@abs_builddir@/results/onek.data';
+COPY onek FROM :'filename';
 SELECT unique1 FROM onek WHERE unique1 < 2 ORDER BY unique1;
  unique1 
 ---------
@@ -52,7 +56,7 @@ SELECT unique1 FROM onek WHERE unique1 < 2 ORDER BY unique1;
 (2 rows)
 
 DELETE FROM onek2;
-COPY onek2 FROM '@abs_builddir@/results/onek.data';
+COPY onek2 FROM :'filename';
 SELECT unique1 FROM onek2 WHERE unique1 < 2 ORDER BY unique1;
  unique1 
 ---------
@@ -60,9 +64,10 @@ SELECT unique1 FROM onek2 WHERE unique1 < 2 ORDER BY unique1;
        1
 (2 rows)
 
-COPY BINARY stud_emp TO '@abs_builddir@/results/stud_emp.data';
+\set filename :abs_builddir '/results/stud_emp.data'
+COPY BINARY stud_emp TO :'filename';
 DELETE FROM stud_emp;
-COPY BINARY stud_emp FROM '@abs_builddir@/results/stud_emp.data';
+COPY BINARY stud_emp FROM :'filename';
 SELECT * FROM stud_emp;
  name  | age |  location  | salary | manager | gpa | percent 
 -------+-----+------------+--------+---------+-----+---------
diff --git a/src/test/regress/output/tablespace.source b/src/test/regress/output/tablespace.source
index 1bbe7e0323..864f4b6e20 100644
--- a/src/test/regress/output/tablespace.source
+++ b/src/test/regress/output/tablespace.source
@@ -1,7 +1,10 @@
+-- directory paths are passed to us in environment variables
+\getenv abs_builddir PG_ABS_BUILDDIR
+\set testtablespace :abs_builddir '/testtablespace'
 -- create a tablespace using WITH clause
-CREATE TABLESPACE regress_tblspacewith LOCATION '@testtablespace@' WITH (some_nonexistent_parameter = true); -- fail
+CREATE TABLESPACE regress_tblspacewith LOCATION :'testtablespace' WITH (some_nonexistent_parameter = true); -- fail
 ERROR:  unrecognized parameter "some_nonexistent_parameter"
-CREATE TABLESPACE regress_tblspacewith LOCATION '@testtablespace@' WITH (random_page_cost = 3.0); -- ok
+CREATE TABLESPACE regress_tblspacewith LOCATION :'testtablespace' WITH (random_page_cost = 3.0); -- ok
 -- check to see the parameter was used
 SELECT spcoptions FROM pg_tablespace WHERE spcname = 'regress_tblspacewith';
        spcoptions       
@@ -12,7 +15,7 @@ SELECT spcoptions FROM pg_tablespace WHERE spcname = 'regress_tblspacewith';
 -- drop the tablespace so we can re-use the location
 DROP TABLESPACE regress_tblspacewith;
 -- create a tablespace we can use
-CREATE TABLESPACE regress_tblspace LOCATION '@testtablespace@';
+CREATE TABLESPACE regress_tblspace LOCATION :'testtablespace';
 -- try setting and resetting some properties for the new tablespace
 ALTER TABLESPACE regress_tblspace SET (random_page_cost = 1.0, seq_page_cost = 1.1);
 ALTER TABLESPACE regress_tblspace SET (some_nonexistent_parameter = true);  -- fail
diff --git a/src/test/regress/pg_regress.c b/src/test/regress/pg_regress.c
index 2c8a600bad..c2fcff55bf 100644
--- a/src/test/regress/pg_regress.c
+++ b/src/test/regress/pg_regress.c
@@ -746,6 +746,14 @@ initialize_environment(void)
 	 */
 	setenv("PGAPPNAME", "pg_regress", 1);
 
+	/*
+	 * Set variables that the test scripts may need to refer to.
+	 */
+	setenv("PG_ABS_SRCDIR", inputdir, 1);
+	setenv("PG_ABS_BUILDDIR", outputdir, 1);
+	setenv("PG_LIBDIR", dlpath, 1);
+	setenv("PG_DLSUFFIX", DLSUFFIX, 1);
+
 	if (nolocale)
 	{
 		/*