+case "$opsys" in
+ sol2)
+ { test "$extra_verbose" = "yes" && cat << \EOF
+ Defining __EXTENSIONS__
+EOF
+cat >> confdefs.h <<\EOF
+#define __EXTENSIONS__ 1
+EOF
+}
+
+ if test "$os_release" -ge 55; then
+ { test "$extra_verbose" = "yes" && cat << \EOF
+ Defining _XOPEN_SOURCE = 500
+EOF
+cat >> confdefs.h <<\EOF
+#define _XOPEN_SOURCE 500
+EOF
+}
+
+ { test "$extra_verbose" = "yes" && cat << \EOF
+ Defining _XOPEN_SOURCE_EXTENDED
+EOF
+cat >> confdefs.h <<\EOF
+#define _XOPEN_SOURCE_EXTENDED 1
+EOF
+}
+
+ fi ;;
+ linux)
+ { test "$extra_verbose" = "yes" && cat << \EOF
+ Defining _POSIX_C_SOURCE = 199506L
+EOF
+cat >> confdefs.h <<\EOF
+#define _POSIX_C_SOURCE 199506L
+EOF
+}
+
+ { test "$extra_verbose" = "yes" && cat << \EOF
+ Defining _XOPEN_SOURCE = 500
+EOF
+cat >> confdefs.h <<\EOF
+#define _XOPEN_SOURCE 500
+EOF
+}
+
+ { test "$extra_verbose" = "yes" && cat << \EOF
+ Defining _XOPEN_SOURCE_EXTENDED
+EOF
+cat >> confdefs.h <<\EOF
+#define _XOPEN_SOURCE_EXTENDED 1
+EOF
+}
+
+ ;;
+esac