diff --git a/lib/areadlink-with-size.c b/lib/areadlink-with-size.c
index eacad3f..2fbe51c 100644
--- a/lib/areadlink-with-size.c
+++ b/lib/areadlink-with-size.c
@@ -36,14 +36,15 @@
    check, so it's OK to guess too small on hosts where there is no
    arbitrary limit to symbolic link length.  */
 #ifndef SYMLINK_MAX
-# define SYMLINK_MAX 1024
+# define SYMLINK_MAX 1023
 #endif
 
 #define MAXSIZE (SIZE_MAX < SSIZE_MAX ? SIZE_MAX : SSIZE_MAX)
 
 /* Call readlink to get the symbolic link value of FILE.
    SIZE is a hint as to how long the link is expected to be;
-   typically it is taken from st_size.  It need not be correct.
+   typically it is taken from st_size.  It need not be correct,
+   and a value of 0 (or more than 8Ki) will select an appropriate lower bound.
    Return a pointer to that NUL-terminated string in malloc'd storage.
    If readlink fails, malloc fails, or if the link value is longer
    than SSIZE_MAX, return NULL (caller may use errno to diagnose).  */
@@ -61,7 +62,7 @@ areadlink_with_size (char const *file, size_t size)
                           : INITIAL_LIMIT_BOUND);
 
   /* The initial buffer size for the link value.  */
-  size_t buf_size = size < initial_limit ? size + 1 : initial_limit;
+  size_t buf_size = size && size < initial_limit ? size + 1 : initial_limit;
 
   while (1)
     {