diff --git a/bin/tests/system/conf.sh.in b/bin/tests/system/conf.sh.in
index 4271f67c30..ada6f04a5c 100644
--- a/bin/tests/system/conf.sh.in
+++ b/bin/tests/system/conf.sh.in
@@ -289,13 +289,78 @@ keyfile_to_managed_keys() {
     keyfile_to_keys_section "managed-keys" "initial-key " $*
 }
 
-# nextpart: read everything that's been appended to a file since the
-# last time 'nextpart' was called.
-nextpart () {
-    [ -f $1.prev ] || echo "0" > $1.prev
+# nextpart*() - functions for reading files incrementally
+#
+# These functions aim to facilitate looking for (or waiting for)
+# messages which may be logged more than once throughout the lifetime of
+# a given named instance by outputting just the part of the file which
+# has been appended since the last time we read it.
+#
+# Calling some of these functions causes temporary *.prev files to be
+# created that need to be cleaned up manually (usually by a given system
+# test's clean.sh script).
+#
+# Note that unlike other nextpart*() functions, nextpartread() is not
+# meant to be directly used in system tests; its sole purpose is to
+# reduce code duplication below.
+#
+# A quick usage example:
+#
+#     $ echo line1 > named.log
+#     $ echo line2 >> named.log
+#     $ nextpart named.log
+#     line1
+#     line2
+#     $ echo line3 >> named.log
+#     $ nextpart named.log
+#     line3
+#     $ nextpart named.log
+#     $ echo line4 >> named.log
+#     $ nextpartpeek named.log
+#     line4
+#     $ nextpartpeek named.log
+#     line4
+#     $ nextpartreset named.log
+#     $ nextpartpeek named.log
+#     line1
+#     line2
+#     line3
+#     line4
+#     $ nextpart named.log
+#     line1
+#     line2
+#     line3
+#     line4
+#     $ nextpart named.log
+#     $
+
+# nextpartreset: reset the marker used by nextpart() and nextpartpeek()
+# so that it points to the start of the given file
+nextpartreset() {
+    echo "0" > $1.prev
+}
+
+# nextpartread: read everything that's been appended to a file since the
+# last time nextpart() was called and print it to stdout, print the
+# total number of lines read from that file so far to stderr
+nextpartread() {
+    [ -f $1.prev ] || nextpartreset $1
     prev=`cat $1.prev`
     awk "NR > $prev "'{ print }
-         END          { print NR > "/dev/stderr" }' $1 2> $1.prev
+         END          { print NR > "/dev/stderr" }' $1
+}
+
+# nextpart: read everything that's been appended to a file since the
+# last time nextpart() was called
+nextpart() {
+	nextpartread $1 2> $1.prev.tmp
+	mv $1.prev.tmp $1.prev
+}
+
+# nextpartpeek: read everything that's been appended to a file since the
+# last time nextpart() was called
+nextpartpeek() {
+	nextpartread $1 2> /dev/null
 }
 
 # copy_setports - Copy Configuration File and Replace Ports
diff --git a/bin/tests/system/conf.sh.win32 b/bin/tests/system/conf.sh.win32
index 07abc52d5a..0c3ef19f09 100644
--- a/bin/tests/system/conf.sh.win32
+++ b/bin/tests/system/conf.sh.win32
@@ -266,13 +266,78 @@ keyfile_to_managed_keys() {
     keyfile_to_keys_section "managed-keys" "initial-key " $*
 }
 
-# nextpart: read everything that's been appended to a file since the
-# last time 'nextpart' was called.
-nextpart () {
-    [ -f $1.prev ] || echo "0" > $1.prev
+# nextpart*() - functions for reading files incrementally
+#
+# These functions aim to facilitate looking for (or waiting for)
+# messages which may be logged more than once throughout the lifetime of
+# a given named instance by outputting just the part of the file which
+# has been appended since the last time we read it.
+#
+# Calling some of these functions causes temporary *.prev files to be
+# created that need to be cleaned up manually (usually by a given system
+# test's clean.sh script).
+#
+# Note that unlike other nextpart*() functions, nextpartread() is not
+# meant to be directly used in system tests; its sole purpose is to
+# reduce code duplication below.
+#
+# A quick usage example:
+#
+#     $ echo line1 > named.log
+#     $ echo line2 >> named.log
+#     $ nextpart named.log
+#     line1
+#     line2
+#     $ echo line3 >> named.log
+#     $ nextpart named.log
+#     line3
+#     $ nextpart named.log
+#     $ echo line4 >> named.log
+#     $ nextpartpeek named.log
+#     line4
+#     $ nextpartpeek named.log
+#     line4
+#     $ nextpartreset named.log
+#     $ nextpartpeek named.log
+#     line1
+#     line2
+#     line3
+#     line4
+#     $ nextpart named.log
+#     line1
+#     line2
+#     line3
+#     line4
+#     $ nextpart named.log
+#     $
+
+# nextpartreset: reset the marker used by nextpart() and nextpartpeek()
+# so that it points to the start of the given file
+nextpartreset() {
+    echo "0" > $1.prev
+}
+
+# nextpartread: read everything that's been appended to a file since the
+# last time 'nextpart' was called and print it to stdout, print the
+# total number of lines read from that file so far to stderr
+nextpartread() {
+    [ -f $1.prev ] || nextpartreset $1
     prev=`cat $1.prev`
     awk "NR > $prev "'{ print }
-         END          { print NR > "/dev/stderr" }' $1 2> $1.prev
+         END          { print NR > "/dev/stderr" }' $1
+}
+
+# nextpart: read everything that's been appended to a file since the
+# last time 'nextpart' was called
+nextpart() {
+	nextpartread $1 2> $1.prev.tmp
+	mv $1.prev.tmp $1.prev
+}
+
+# nextpartpeek: read everything that's been appended to a file since the
+# last time 'nextpart' was called
+nextpartpeek() {
+	nextpartread $1 2> /dev/null
 }
 
 # copy_setports - Copy Configuration File and Replace Ports