detect hostname binary before acturally executing it

postfix.spec

@@ -23,7 +23,7 @@
 Name:           postfix
 Summary:        Postfix Mail Transport Agent
 Version:        3.7.2
-Release:        2
+Release:        3
 Epoch:          2
 URL:            http://www.postfix.org
 License:        (IPL-1.0 and GPLv2+) or (EPL-2.0 and GPLv2+)
@@ -372,8 +372,12 @@ if [ ! -f %{sslkey} ]; then
 fi
 
 if [ ! -f %{sslcert} ]; then
-  FQDN=`hostname`
+  if [ -x %{_bindir}/hostname ] ; then
-  if [ "x${FQDN}" = "x" ]; then
+    FQDN=`hostname`
+    if [ "x${FQDN}" = "x" ]; then
+      FQDN=localhost.localdomain
+    fi
+  else
     FQDN=localhost.localdomain
   fi
 
@@ -551,6 +555,12 @@ fi
 %{postfix_doc_dir}/README_FILES/*
 
 %changelog
+* Fri Sep 30 2022 Funda Wang <fundawang@yeah.net> - 2:3.7.2-3
+- Type:bugfix
+- ID:NA
+- SUG:NA
+- DESC:detect if hostname is executable before executing it
+
 * Tue Sep 13 2022 xingwei <xingwei14@h-partners.com> - 2:3.7.2-2
 - Type:bugfix
 - ID:NA