diff -r 947843245525 -r e7e56c56d126 ucx/string.h
--- a/ucx/string.h	Thu Oct 15 16:36:07 2015 +0200
+++ b/ucx/string.h	Thu Oct 15 16:55:10 2015 +0200
@@ -383,6 +383,56 @@
  */
 int sstrsuffix(sstr_t string, sstr_t suffix);
 
+/**
+ * Returns a lower case version of a string.
+ * 
+ * This function creates a duplicate of the input string, first. See the
+ * documentation of sstrdup() for the implications.
+ * 
+ * @param string the input string
+ * @return the resulting lower case string
+ * @see sstrdup()
+ */
+sstr_t sstrlower(sstr_t string);
+
+/**
+ * Returns a lower case version of a string.
+ * 
+ * This function creates a duplicate of the input string, first. See the
+ * documentation of sstrdup_a() for the implications.
+ * 
+ * @param allocator the allocator used for duplicating the string
+ * @param string the input string
+ * @return the resulting lower case string
+ * @see sstrdup_a()
+ */
+sstr_t sstrlower_a(UcxAllocator *allocator, sstr_t string);
+
+/**
+ * Returns a upper case version of a string.
+ * 
+ * This function creates a duplicate of the input string, first. See the
+ * documentation of sstrdup() for the implications.
+ * 
+ * @param string the input string
+ * @return the resulting upper case string
+ * @see sstrdup()
+ */
+sstr_t sstrupper(sstr_t string);
+
+/**
+ * Returns a upper case version of a string.
+ * 
+ * This function creates a duplicate of the input string, first. See the
+ * documentation of sstrdup_a() for the implications.
+ * 
+ * @param allocator the allocator used for duplicating the string
+ * @param string the input string
+ * @return the resulting upper case string
+ * @see sstrdup_a()
+ */
+sstr_t sstrupper_a(UcxAllocator *allocator, sstr_t string);
+
 #ifdef	__cplusplus
 }
 #endif