#define REF_ISBROKEN 0x04
/*
- * Calls the specified function for each ref file until it returns nonzero,
- * and returns the value
+ * Calls the specified function for each ref file until it returns
+ * nonzero, and returns the value. Please note that it is not safe to
+ * modify references while an iteration is in progress, unless the
+ * same callback function invocation that modifies the reference also
+ * returns a nonzero value to immediately stop the iteration.
*/
typedef int each_ref_fn(const char *refname, const unsigned char *sha1, int flags, void *cb_data);
extern int head_ref(each_ref_fn, void *);