diff --git a/include/string.h b/include/string.h
index 4aa930e..cd09513 100644
--- a/include/string.h
+++ b/include/string.h
@@ -14,7 +14,7 @@ extern "C" {
 
 #define __NEED_size_t
 #if defined(_POSIX_SOURCE) || defined(_POSIX_C_SOURCE) \
- || defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE)
+ || defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
 #define __NEED_locale_t
 #endif
 
@@ -53,7 +53,7 @@ char *strerror (int);
 
 
 #if defined(_POSIX_SOURCE) || defined(_POSIX_C_SOURCE) \
- || defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE)
+ || defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
 char *strtok_r (char *, const char *, char **);
 int strerror_r (int, char *, size_t);
 char *stpcpy(char *, const char *);
@@ -67,10 +67,21 @@ int strcoll_l (const char *, const char *, locale_t);
 size_t strxfrm_l (char *, const char *, size_t, locale_t);
 #endif
 
-#if defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE)
+#if defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
 void *memccpy (void *, const void *, int, size_t);
 #endif
 
+#if defined(_BSD_SOURCE) || defined(_GNU_SOURCE)
+int bcmp (const void *, const void *, size_t);
+void bcopy (const void *, void *, size_t);
+void bzero (void *, size_t);
+int strcasecmp (const char *, const char *);
+int strncasecmp (const char *, const char *, size_t);
+char *index (const char *, int);
+char *rindex (const char *, int);
+int ffs (int);
+#endif
+
 #ifdef _BSD_SOURCE
 size_t strlcat (char *, const char *, size_t);
 size_t strlcpy (char *, const char *, size_t);
@@ -78,8 +89,8 @@ size_t strlcpy (char *, const char *, size_t);
 
 #ifdef _GNU_SOURCE
 int strverscmp (const char *, const char *);
-int strcasecmp (const char *, const char *);
-int strncasecmp (const char *, const char *, size_t);
+int strcasecmp_l (const char *, const char *, locale_t);
+int strncasecmp_l (const char *, const char *, size_t, locale_t);
 char *strchrnul(const char *, int);
 char *strcasestr(const char *, const char *);
 char *strsep(char **, const char *);