diff --git a/doc/src/sgml/func/func-matching.sgml b/doc/src/sgml/func/func-matching.sgml
index af60e9898de..ae1dff66722 100644
--- a/doc/src/sgml/func/func-matching.sgml
+++ b/doc/src/sgml/func/func-matching.sgml
@@ -505,7 +505,7 @@ substring('foobar' SIMILAR '#"o_b#"%' ESCAPE '#')    <lineannotation>NULL</linea
      <acronym>POSIX</acronym> regular expressions provide a more
      powerful means for pattern matching than the <function>LIKE</function> and
      <function>SIMILAR TO</function> operators.
-     Many Unix tools such as <command>egrep</command>,
+     Many Unix tools such as <command>grep -E</command>,
      <command>sed</command>, or <command>awk</command> use a pattern
      matching language that is similar to the one described here.
     </para>
@@ -1065,7 +1065,7 @@ regexp_substr('ABCDEFGHI', '(c..)(...)', 1, 1, 'i', 2)
     Regular expressions (<acronym>RE</acronym>s), as defined in
     <acronym>POSIX</acronym> 1003.2, come in two forms:
     <firstterm>extended</firstterm> <acronym>RE</acronym>s or <acronym>ERE</acronym>s
-    (roughly those of <command>egrep</command>), and
+    (roughly those of <command>grep -E</command>), and
     <firstterm>basic</firstterm> <acronym>RE</acronym>s or <acronym>BRE</acronym>s
     (roughly those of <command>ed</command>).
     <productname>PostgreSQL</productname> supports both forms, and
diff --git a/src/tools/find_typedef b/src/tools/find_typedef
index 24e9b76651d..fec0520c32e 100755
--- a/src/tools/find_typedef
+++ b/src/tools/find_typedef
@@ -36,12 +36,12 @@ do	# if objdump -W is recognized, only one line of error should appear
 	if [ `objdump -W 2>&1 | wc -l` -eq 1 ]
 	then	# Linux
 		objdump -W "$DIR"/* |
-		egrep -A3 '\(DW_TAG_typedef\)' |
+		grep -E -A3 '\(DW_TAG_typedef\)' |
 		awk ' $2 == "DW_AT_name" {print $NF}'
 	elif [ `readelf -w 2>&1 | wc -l` -gt 1 ]
 	then	# FreeBSD, similar output to Linux
 		readelf -w "$DIR"/* |
-		egrep -A3 '\(DW_TAG_typedef\)' |
+		grep -E -A3 '\(DW_TAG_typedef\)' |
 		awk ' $1 == "DW_AT_name" {print $NF}'
 	fi
 done |
@@ -50,4 +50,4 @@ sort |
 uniq |
 # these are used both for typedefs and variable names
 # so do not include them
-egrep -v '^(date|interval|timestamp|ANY)$'
+grep -E -v '^(date|interval|timestamp|ANY)$'
diff --git a/src/tools/perlcheck/find_perl_files b/src/tools/perlcheck/find_perl_files
index 20dceb800d0..406ec7f3a08 100644
--- a/src/tools/perlcheck/find_perl_files
+++ b/src/tools/perlcheck/find_perl_files
@@ -12,7 +12,7 @@ find_perl_files () {
 		find "$@" -type f -name '*.p[lm]' -print
 		# take executable files that file(1) thinks are perl files
 		find "$@" -type f -perm -100 -exec file {} \; -print |
-		egrep -i ':.*perl[0-9]*\>' |
+		grep -E -i ':.*perl[0-9]*\>' |
 		cut -d: -f1
 	} | sort -u | grep -v '^\./\.git/'
 }