patch 7.4.1380
Problem:    The job exit callback is not implemented.
Solution:   Add the "exit-cb" option.
diff --git a/src/structs.h b/src/structs.h
index 56b698c..b67f48a 100644
--- a/src/structs.h
+++ b/src/structs.h
@@ -1265,6 +1265,7 @@
 #endif
     jobstatus_T	jv_status;
     char_u	*jv_stoponexit; /* allocated */
+    char_u	*jv_exit_cb;	/* allocated */
 
     int		jv_refcount;	/* reference count */
     channel_T	*jv_channel;	/* channel for I/O, reference counted */
@@ -1390,6 +1391,7 @@
 #define JO_PART		0x0800	/* "part" */
 #define JO_ID		0x1000	/* "id" */
 #define JO_STOPONEXIT	0x2000	/* "stoponexit" */
+#define JO_EXIT_CB	0x4000	/* "exit-cb" */
 #define JO_ALL		0xffffff
 
 #define JO_MODE_ALL	(JO_MODE + JO_IN_MODE + JO_OUT_MODE + JO_ERR_MODE)
@@ -1418,6 +1420,8 @@
     int		jo_id;
     char_u	jo_soe_buf[NUMBUFLEN];
     char_u	*jo_stoponexit;
+    char_u	jo_ecb_buf[NUMBUFLEN];
+    char_u	*jo_exit_cb;
 } jobopt_T;