1 files changed, 41 insertions, 0 deletions
diff --git a/src/wchar/wcsstarts.c b/src/wchar/wcsstarts.c
new file mode 100644
index 0000000..0b000af
--- /dev/null
+++ b/src/wchar/wcsstarts.c
@@ -0,0 +1,41 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <wchar.h>
+
+
+
+/**
+ * Check whether a string starts with a specific string.
+ * This check is case sensitive.
+ * 
+ * This is a slibc extension.
+ * 
+ * @param   string   The string to inspect.
+ * @param   desired  The desired beginning of the string.
+ * @return           `string` if `string` begins with
+ *                   `desired`, `NULL` otherwise.
+ */
+wchar_t* (wcsstarts)(const wchar_t* string, const wchar_t* desired)
+{
+  size_t n = wcslen(string);
+  size_t m = wcslen(desired);
+  if (n < m)
+    return NULL;
+  return wmemcmp(string, desired, m) ? NULL : string;
+}
+