1 files changed, 20 insertions, 0 deletions
diff --git a/sys/libbio/phylo.c b/sys/libbio/phylo.c
new file mode 100644
index 0000000..8033e35
--- /dev/null
+++ b/sys/libbio/phylo.c
@@ -0,0 +1,20 @@
+#include <u.h>
+#include <libn.h>
+#include <libbio.h>
+
+error
+phylo·addchild(bio·Node* parent, bio·Node* child)
+{
+    bio·Node *it, *sibling;
+    if (parent->nchild < 2) {
+        parent->child[parent->nchild++] = child;
+    } else {
+        for (it = parent->child[1]->sibling; it != nil; it = it->sibling) {
+            sibling = it;
+        }
+        sibling->sibling = child;
+        parent->nchild++;
+    }
+
+    return 0;
+}