--- /dev/null
+#include "config.h"
+#include <stdio.h>
+#include <string.h>
+
+/**
+ * tal/stack - stack of tal contextes (inspired by talloc_stack)
+ *
+ * Implement a stack of tal contexts. A new (empty) context is pushed on top
+ * of the stack using tal_newframe and it is popped/freed using tal_free().
+ * tal_curframe() can be used to get the stack's top context.
+ *
+ * tal_stack can be used to implement per-function temporary allocation context
+ * to help mitigating memory leaks, but unlike the plain tal approach it does not
+ * require the caller to pass a destination context for returning allocated
+ * values. Instead, allocated values are moved to the parent context using
+ * tal_steal(tal_parent(tmp_ctx), ptr).
+ *
+ * Example:
+ * #include <assert.h>
+ * #include <ccan/tal/stack/stack.h>
+ *
+ * static int *do_work(void)
+ * {
+ * int *retval = NULL;
+ * tal_t *tmp_ctx = tal_newframe();
+ *
+ * int *val = talz(tmp_ctx, int);
+ * assert(val != NULL);
+ *
+ * // ... do something with val ...
+ *
+ * if (retval >= 0) {
+ * // steal to parent cxt so it survives tal_free()
+ * tal_steal(tal_parent(tmp_ctx), val);
+ * retval = val;
+ * }
+ * tal_free(tmp_ctx);
+ * return retval;
+ * }
+ *
+ * int main(int argc, char *argv[])
+ * {
+ * tal_t *tmp_ctx = tal_newframe();
+ * int *val = do_work();
+ * if (val) {
+ * // ... do something with val ...
+ * }
+ * // val is eventually freed
+ * tal_free(tmp_ctx);
+ * return 0;
+ * }
+ *
+ * License: BSD-MIT
+ * Author: Delio Brignoli <brignoli.delio@gmail.com>
+ */
+int main(int argc, char *argv[])
+{
+ /* Expect exactly one argument */
+ if (argc != 2)
+ return 1;
+
+ if (strcmp(argv[1], "depends") == 0) {
+ printf("ccan/tal\n");
+ return 0;
+ }
+
+ return 1;
+}