fixed mac issues

ax_init_standard_project.m4

@@ -65,7 +65,7 @@ AC_DEFUN([AX_ADD_MAKEFILE_TARGET_DEP], [
 #     $1 = variable name
 AC_DEFUN([AX_SUBST], [
   AC_SUBST([$1])
-  tmp_var=$(echo "${$1}" | sed ':a;N;$!ba;s/\n/\\n/g')
+  tmp_var=$(echo "${$1}" | awk 1 ORS='\\n')
   tmp_var=${tmp_var//\"/\\\"}
   tmp_var=${tmp_var//\'/\'\"\'\"\'}
   tmp_var=${tmp_var//#/\\#}
@@ -364,10 +364,10 @@ AC_DEFUN([AX_PKG_REQUIRE], [
       done
       if test ${$1_found} -eq 0; then
         for p in /usr/include ${$1_CFLAGS}; do
-          $1_file=$(find ${p\#-I} -name $3)
-          if test -e ${$1_file}; then
-            AC_MSG_WARN([Header file $3 found in ${$1_file%/$3}])
-            $1_CFLAGS="${$1_CFLAGS} -I${p\#-I}/${$1_file%/$3}"
+          $1_file=$(find ${p#-I} -name $3)
+          if test -e "${$1_file}"; then
+            AC_MSG_NOTICE([Header file $3 found in sub path as ${$1_file}])
+            $1_CFLAGS="${$1_CFLAGS} -I${$1_file%/$3}"
             $1_found=1
             break
           fi
@@ -397,7 +397,8 @@ AC_DEFUN([AX_PKG_REQUIRE], [
               for p in /usr/include ${$1_CFLAGS}; do
                 $1_file=$(find ${p#-I} -name $3)
                 if test -e ${$1_file}; then
-                  $1_CFLAGS="${$1_CFLAGS} -I${$1_file%/*}"
+		  AC_MSG_NOTICE([Header file $3 found in sub path as ${$1_file}])
+                  $1_CFLAGS="${$1_CFLAGS} -I${$1_file%/$3}"
                   $1_found=1
                   break
                 fi