Clarify strtok_r() description.

diff --git a/src/lib/string.c b/src/lib/string.c
index bec4444670b025768485cb143edb0329de3cb60c..cb042f02242d02a2090f6566016fb45f67c0df21 100644 (file)
--- a/src/lib/string.c
+++ b/src/lib/string.c
@@ -212,7 +212,9 @@ strstr (const char *haystack, const char *needle)
    single string.
 
    strtok_r() modifies the string S, changing delimiters to null
-   bytes.  Thus, S must be a modifiable string.
+   bytes.  Thus, S must be a modifiable string.  String literals,
+   in particular, are *not* modifiable in C, even though for
+   backward compatibility they are not `const'.
 
    Example usage: