the backticks are the old way of doing subshells, use the new format

reposync/runreposync.sh

@@ -24,8 +24,8 @@ echo "Inputs: REPOID=\"$REPOID\" REPOFILE=\"$REPOFILE\" REPOPATH=\"$REPOPATH\" C
 REPOPATH="/repo/${REPOPATH}"
 # Record what's already there first
 /usr/bin/find ${REPOPATH} -type f -name "*.rpm" ! -size 0 -printf '%f %s\n' > /tmp/prelist
-PRECOUNT=`wc -l /tmp/prelist | cut -d' ' -f1`
-PRESIZE=`awk '{print $2}' /tmp/prelist | paste -sd+ | bc`
+PRECOUNT=$(wc -l /tmp/prelist | cut -d' ' -f1)
+PRESIZE=$(awk '{print $2}' /tmp/prelist | paste -sd+ | bc)
 
 echo "[${REPOID}]" > /etc/yum.repos.d/sync.repo
 echo $REPOFILE | base64 -d >> /etc/yum.repos.d/sync.repo
@@ -112,12 +112,12 @@ if [ $? -eq 0 ]; then
 fi
 # Now let's look at the new stuff
 /usr/bin/find ${REPOPATH} -type f -name "*.rpm" ! -size 0 -printf '%f %s\n' > /tmp/postlist
-POSTCOUNT=`wc -l /tmp/postlist | cut -d' ' -f1`
+POSTCOUNT=$(wc -l /tmp/postlist | cut -d' ' -f1)
 
 # cdn.redhat.com delivers us some rpms with junk attached at the end ... ?
 # these are 'useable' but since the size changes, metadata must be regenerated to
 # take it into account.
-POSTSIZE=`awk '{print $2}' /tmp/postlist | paste -sd+ | bc`
+POSTSIZE=$(awk '{print $2}' /tmp/postlist | paste -sd+ | bc)
 
 if [[ ($PRECOUNT -eq $POSTCOUNT) && ($PRESIZE -ne $POSTSIZE) ]]; then
   cat << EOF | error | tee $OUTPUT
@@ -126,11 +126,11 @@ EOF
 fi
 
 if [[ ($PRECOUNT -ne $POSTCOUNT) || ($PRESIZE -ne $POSTSIZE) ]]; then
-  CHANGELIST=`/usr/bin/diff --changed-group-format='%>' --unchanged-group-format='' <(awk '{print $1}' /tmp/prelist) <(awk '{print $1}' /tmp/postlist)`
+  CHANGELIST=$(/usr/bin/diff --changed-group-format='%>' --unchanged-group-format='' <(awk '{print $1}' /tmp/prelist) <(awk '{print $1}' /tmp/postlist))
 
   # Run createrepo
   if [[ $RUN_CREATEREPO -eq 1 ]]; then
-    COMPXMLFILE=`/bin/ls -1tr ${REPOPATH}/*-comps*xml.gz  2>&1 | /usr/bin/tail -1`
+    COMPXMLFILE=$(/bin/ls -1tr ${REPOPATH}/*-comps*xml.gz  2>&1 | /usr/bin/tail -1)
 
     if [ -f "$COMPXMLFILE" ]; then
       /bin/cp -f $COMPXMLFILE $REPOPATH/comps.xml.gz
@@ -180,11 +180,11 @@ fi
 
 
 for rpm in ${CHANGELIST}; do
-  path=`/usr/bin/find ${REPOPATH} -type f -name "${rpm}"`
-  info=`/usr/bin/rpm --queryformat "%{NAME} %{VERSION}-%{RELEASE} %{ARCH}" -qp ${path} 2>/dev/null`
-  name=`echo $info | cut -d' ' -f1`
-  version=`echo $info | cut -d' ' -f2`
-  arch=`echo $info | cut -d' ' -f3`
+  path=$(/usr/bin/find ${REPOPATH} -type f -name "${rpm}")
+  info=$(/usr/bin/rpm --queryformat "%{NAME} %{VERSION}-%{RELEASE} %{ARCH}" -qp ${path} 2>/dev/null)
+  name=$(echo $info | cut -d' ' -f1)
+  version=$(echo $info | cut -d' ' -f2)
+  arch=$(echo $info | cut -d' ' -f3)
 
   cat << EOF | log
     "message_type": "change",
@@ -206,7 +206,7 @@ cat << EOF | log
 EOF
 
 # Turn the new-line separated list of changes into a comma-separated list of quoted strings
-LIST=`sed 's/^/"/;s/$/"/;s/^""$//' <(echo "${CHANGELIST}") | /usr/bin/tr '\n' ',' | sed 's/,$//'`
+LIST=$(sed 's/^/"/;s/$/"/;s/^""$//' <(echo "${CHANGELIST}") | /usr/bin/tr '\n' ',' | sed 's/,$//')
 
 cat << EOF | log > $OUTPUT
   "message_type": "result",