From dfe4488e88c148fcb950f4814e3299146119cd3c Mon Sep 17 00:00:00 2001
From: Thanh Son Phung <tphung@nd.edu>
Date: Wed, 6 Nov 2024 16:13:13 -0500
Subject: [PATCH 1/9] scheduling with library protocol version checked

---
 taskvine/src/manager/vine_manager.c     | 7 +++++--
 taskvine/src/manager/vine_protocol.h    | 4 +++-
 taskvine/src/manager/vine_schedule.c    | 7 +++++++
 taskvine/src/manager/vine_worker_info.h | 3 +++
 taskvine/src/worker/vine_worker.c       | 3 ++-
 5 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/taskvine/src/manager/vine_manager.c b/taskvine/src/manager/vine_manager.c
index 946d1132f7..190e6c9639 100644
--- a/taskvine/src/manager/vine_manager.c
+++ b/taskvine/src/manager/vine_manager.c
@@ -1461,9 +1461,10 @@ static vine_msg_code_t handle_taskvine(struct vine_manager *q, struct vine_worke
 {
 	char items[4][VINE_LINE_MAX];
 	int worker_protocol;
+	int worker_library_protocol;
 
-	int n = sscanf(line, "taskvine %d %s %s %s %s", &worker_protocol, items[0], items[1], items[2], items[3]);
-	if (n != 5)
+	int n = sscanf(line, "taskvine %d %d %s %s %s %s", &worker_protocol, &worker_library_protocol, items[0], items[1], items[2], items[3]);
+	if (n != 6)
 		return VINE_MSG_FAILURE;
 
 	if (worker_protocol != VINE_PROTOCOL_VERSION) {
@@ -1472,6 +1473,8 @@ static vine_msg_code_t handle_taskvine(struct vine_manager *q, struct vine_worke
 		return VINE_MSG_FAILURE;
 	}
 
+	w->library_protocol_version = worker_library_protocol;
+
 	if (w->hostname)
 		free(w->hostname);
 	if (w->os)
diff --git a/taskvine/src/manager/vine_protocol.h b/taskvine/src/manager/vine_protocol.h
index 7a3dca9fcd..d32c495d1f 100644
--- a/taskvine/src/manager/vine_protocol.h
+++ b/taskvine/src/manager/vine_protocol.h
@@ -13,7 +13,9 @@ worker, and catalog, but should not be visible to the public user API.
 #ifndef VINE_PROTOCOL_H
 #define VINE_PROTOCOL_H
 
-#define VINE_PROTOCOL_VERSION 11
+#define VINE_PROTOCOL_VERSION 12
+
+#define VINE_LIBRARY_PROTOCOL_VERSION 1
 
 #define VINE_LINE_MAX 4096       /**< Maximum length of a vine message line. */
 
diff --git a/taskvine/src/manager/vine_schedule.c b/taskvine/src/manager/vine_schedule.c
index 1127e1e636..7975e8964a 100644
--- a/taskvine/src/manager/vine_schedule.c
+++ b/taskvine/src/manager/vine_schedule.c
@@ -10,6 +10,7 @@ See the file COPYING for details.
 #include "vine_file.h"
 #include "vine_file_replica.h"
 #include "vine_mount.h"
+#include "vine_protocol.h"
 
 #include "debug.h"
 #include "hash_table.h"
@@ -203,6 +204,12 @@ int check_worker_against_task(struct vine_manager *q, struct vine_worker_info *w
 		return 0;
 	}
 
+        /* Check if the library and the worker have the same library protocol version. */
+        if (t->provides_library && (w->library_protocol_version != VINE_LIBRARY_PROTOCOL_VERSION)) {
+                debug(D_VINE, "Worker %s can't run library with id %d due to mismatched library protocol version.", w->workerid, t->task_id);
+                return 0;
+        }
+
 	/* Compute the resources to allocate to this task. */
 	struct rmsummary *l = vine_manager_choose_resources_for_task(q, w, t);
 
diff --git a/taskvine/src/manager/vine_worker_info.h b/taskvine/src/manager/vine_worker_info.h
index c52fa91103..d5c9dc7c7d 100644
--- a/taskvine/src/manager/vine_worker_info.h
+++ b/taskvine/src/manager/vine_worker_info.h
@@ -28,6 +28,9 @@ struct vine_worker_info {
 	/* Connection to the worker or other client. */
 	struct link *link;
 
+        /* Library protocol version of this worker. */
+        int library_protocol_version;
+
 	/* Static properties reported by worker when it connects. */
 	char *hostname;
 	char *os;
diff --git a/taskvine/src/worker/vine_worker.c b/taskvine/src/worker/vine_worker.c
index 84f3f3994f..5767c58608 100644
--- a/taskvine/src/worker/vine_worker.c
+++ b/taskvine/src/worker/vine_worker.c
@@ -564,8 +564,9 @@ static void report_worker_ready(struct link *manager)
 	}
 
 	send_async_message(manager,
-			"taskvine %d %s %s %s %d.%d.%d\n",
+			"taskvine %d %d %s %s %s %d.%d.%d\n",
 			VINE_PROTOCOL_VERSION,
+			VINE_LIBRARY_PROTOCOL_VERSION,
 			hostname,
 			options->os_name,
 			options->arch_name,

From 3eca9b827ed9470744247d3aabd5c0030edc7fc7 Mon Sep 17 00:00:00 2001
From: Thanh Son Phung <tphung@nd.edu>
Date: Wed, 6 Nov 2024 16:54:01 -0500
Subject: [PATCH 2/9] add check exec_mode of library to worker

---
 poncho/src/poncho/library_network_code.py | 12 +++++----
 taskvine/src/manager/vine_manager_put.c   |  1 +
 taskvine/src/manager/vine_task.c          | 30 +++++++++++++++++----
 taskvine/src/manager/vine_task.h          |  3 +++
 taskvine/src/worker/vine_worker.c         | 32 +++++++++++++++++++----
 5 files changed, 63 insertions(+), 15 deletions(-)

diff --git a/poncho/src/poncho/library_network_code.py b/poncho/src/poncho/library_network_code.py
index 159d16dd45..29a5ae9238 100755
--- a/poncho/src/poncho/library_network_code.py
+++ b/poncho/src/poncho/library_network_code.py
@@ -379,16 +379,18 @@ def main():
     if context_vars:
         (load_variable_from_library.__globals__).update(context_vars)
 
+    # set execution mode of functions in this library
+    global exec_method
+    exec_method = library_info['exec_mode']
+
     # send configuration of library, just its name for now
     config = {
-        "name": library_info['library_name']
+        "name": library_info['library_name'],
+        "taskid": args.task_id,
+        "exec_mode": exec_method,
     }
     send_configuration(config, out_pipe_fd, args.worker_pid)
 
-    # set execution mode of functions in this library
-    global exec_method
-    exec_method = library_info['exec_mode']
-
     # register sigchld handler to turn a sigchld signal into an I/O event
     signal.signal(signal.SIGCHLD, sigchld_handler)
 
diff --git a/taskvine/src/manager/vine_manager_put.c b/taskvine/src/manager/vine_manager_put.c
index 83dbaeb64f..e8e22b22bf 100644
--- a/taskvine/src/manager/vine_manager_put.c
+++ b/taskvine/src/manager/vine_manager_put.c
@@ -509,6 +509,7 @@ vine_result_code_t vine_manager_put_task(
 	if (t->provides_library) {
 		vine_manager_send(q, w, "provides_library %s\n", t->provides_library);
 		vine_manager_send(q, w, "function_slots %d\n", t->function_slots_total);
+		vine_manager_send(q, w, "func_exec_mode %d\n", t->func_exec_mode);
 	}
 
 	vine_manager_send(q, w, "category %s\n", t->category);
diff --git a/taskvine/src/manager/vine_task.c b/taskvine/src/manager/vine_task.c
index c0ea564b27..d5f10230ed 100644
--- a/taskvine/src/manager/vine_task.c
+++ b/taskvine/src/manager/vine_task.c
@@ -328,11 +328,7 @@ void vine_task_set_function_exec_mode(struct vine_task *t, vine_task_func_exec_m
 void vine_task_set_function_exec_mode_from_string(struct vine_task *t, const char *exec_mode)
 {
 	if (exec_mode && t->provides_library) {
-		if (!strncmp(exec_mode, "fork", strlen("fork"))) {
-			t->func_exec_mode = VINE_TASK_FUNC_EXEC_MODE_FORK;
-		} else {
-			t->func_exec_mode = VINE_TASK_FUNC_EXEC_MODE_DIRECT;
-		}
+                t->func_exec_mode = vine_task_func_exec_mode_from_string(exec_mode);
 	}
 }
 
@@ -1005,3 +1001,27 @@ char *vine_task_to_json(struct vine_task *t)
 	buffer_free(&b);
 	return json;
 }
+
+/* Converts an int64_t to a valid vine_task_func_exec_mode_t.
+ * Returns VINE_TASK_FUNC_EXEC_MODE_INVALID if there's no valid mode for the integer. */
+vine_task_func_exec_mode_t vine_task_func_exec_mode_from_int64_t(int64_t n) {
+        if (n == 1) {
+                return VINE_TASK_FUNC_EXEC_MODE_DIRECT;
+        }
+        if (n == 2) {
+                return VINE_TASK_FUNC_EXEC_MODE_FORK;
+        }
+        return VINE_TASK_FUNC_EXEC_MODE_INVALID;
+}
+
+/* Converts a string to a valid vine_task_func_exec_mode_t.
+ * Returns VINE_TASK_FUNC_EXEC_MODE_INVALID if there's no valid mode for the string. */
+vine_task_func_exec_mode_t vine_task_func_exec_mode_from_string(const char *exec_mode) {
+        if (!strncmp(exec_mode, "direct", strlen("direct"))) {
+                return VINE_TASK_FUNC_EXEC_MODE_DIRECT;
+        }
+        if (!strncmp(exec_mode, "fork", strlen("fork"))) {
+                return VINE_TASK_FUNC_EXEC_MODE_FORK;
+        }
+        return VINE_TASK_FUNC_EXEC_MODE_INVALID;
+}
diff --git a/taskvine/src/manager/vine_task.h b/taskvine/src/manager/vine_task.h
index 4c53ece509..718f46d383 100644
--- a/taskvine/src/manager/vine_task.h
+++ b/taskvine/src/manager/vine_task.h
@@ -164,6 +164,9 @@ const char *vine_task_state_to_string( vine_task_state_t task_state );
 struct jx * vine_task_to_jx( struct vine_manager *q, struct vine_task *t );
 char * vine_task_to_json(struct vine_task *t);
 
+vine_task_func_exec_mode_t vine_task_func_exec_mode_from_int64_t(int64_t n);
+vine_task_func_exec_mode_t vine_task_func_exec_mode_from_string(const char *exec_mode);
+
 
 /** Attach an input or outputs to tasks without declaring files to manager.
  * Only really useful at the worker where tasks are created without a manager. */
diff --git a/taskvine/src/worker/vine_worker.c b/taskvine/src/worker/vine_worker.c
index 5767c58608..8843664607 100644
--- a/taskvine/src/worker/vine_worker.c
+++ b/taskvine/src/worker/vine_worker.c
@@ -866,6 +866,14 @@ static struct vine_task *do_task_body(struct link *manager, int task_id, time_t
 			task->function_slots_requested = n;
 			/* Also set the total number determined by the manager. */
 			task->function_slots_total = n;
+		} else if (sscanf(line, "func_exec_mode %" PRId64, &n) == 1) {
+			func_exec_mode = vine_task_func_exec_mode_from_int64_t(n);
+			if (func_exec_mode == VINE_TASK_FUNC_EXEC_MODE_INVALID) {
+				debug(D_VINE | D_NOTICE, "invalid func_exec_mode from manager: %s", line);
+				vine_task_delete(task);
+				return 0;
+			}
+			task->func_exec_mode = func_exec_mode;
 		} else if (sscanf(line, "infile %s %s %d", localname, taskname_encoded, &flags)) {
 			url_decode(taskname_encoded, taskname, VINE_LINE_MAX);
 			vine_hack_do_not_compute_cached_name = 1;
@@ -1547,10 +1555,25 @@ static int check_library_startup(struct vine_process *p)
 	struct jx *response = jx_parse_string(buffer);
 
 	const char *name = jx_lookup_string(response, "name");
+	const char *taskid = jx_lookup_string(response, "taskid");
+	const char *exec_mode = jx_lookup_string(response, "exec_mode");
+
+	int ok = 1;
+	
+	if (!name || !taskid || !exec_mode) {
+		ok = 0;	
+	}
 
-	int ok = 0;
-	if (!strcmp(name, p->task->provides_library)) {
-		ok = 1;
+	vine_task_func_exec_mode_t converted_exec_mode = vine_task_func_exec_mode_from_string(exec_mode);
+
+	if (p->task->provides_library && strcmp(name, p->task->provides_library)) {
+		ok = 0;
+	}
+	if (taskid != p->task->task_id) {
+		ok = 0;
+	}
+	if (p->task->exec_mode && converted_exec_mode != p->task->exec_mode) {
+		ok = 0;	
 	}
 	if (response) {
 		jx_delete(response);
@@ -1586,8 +1609,7 @@ static void check_libraries_ready(struct link *manager)
 				debug(D_VINE, "Library %s reports ready to execute functions.", library_process->task->provides_library);
 				library_process->library_ready = 1;
 			} else {
-				/* Kill library if the name reported back doesn't match its name or
-				 * if there's any problem. */
+				/* Kill library if it fails the startup check. */
 				debug(D_VINE,
 						"Library %s task id %" PRIu64 " verification failed (unexpected response). Killing it.",
 						library_process->task->provides_library,

From 2e6a830f0a1d0a8dee75b8dbfffa537f9e021950 Mon Sep 17 00:00:00 2001
From: Thanh Son Phung <tphung@nd.edu>
Date: Thu, 7 Nov 2024 09:18:43 -0500
Subject: [PATCH 3/9] fix bug

---
 taskvine/src/manager/vine_task.h  | 3 ++-
 taskvine/src/worker/vine_worker.c | 7 ++++---
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/taskvine/src/manager/vine_task.h b/taskvine/src/manager/vine_task.h
index 718f46d383..13f56bf4d4 100644
--- a/taskvine/src/manager/vine_task.h
+++ b/taskvine/src/manager/vine_task.h
@@ -38,7 +38,8 @@ typedef enum {
 } vine_task_state_t;
 
 typedef enum {
-        VINE_TASK_FUNC_EXEC_MODE_DIRECT = 0,    /**< A library task will execute function calls directly in its process **/
+        VINE_TASK_FUNC_EXEC_MODE_INVALID = -1,
+        VINE_TASK_FUNC_EXEC_MODE_DIRECT = 1,    /**< A library task will execute function calls directly in its process **/
         VINE_TASK_FUNC_EXEC_MODE_FORK,          /**< A library task will fork and execute each function call. **/
 } vine_task_func_exec_mode_t;
 
diff --git a/taskvine/src/worker/vine_worker.c b/taskvine/src/worker/vine_worker.c
index 8843664607..6731a6a225 100644
--- a/taskvine/src/worker/vine_worker.c
+++ b/taskvine/src/worker/vine_worker.c
@@ -867,7 +867,7 @@ static struct vine_task *do_task_body(struct link *manager, int task_id, time_t
 			/* Also set the total number determined by the manager. */
 			task->function_slots_total = n;
 		} else if (sscanf(line, "func_exec_mode %" PRId64, &n) == 1) {
-			func_exec_mode = vine_task_func_exec_mode_from_int64_t(n);
+			vine_task_func_exec_mode_t func_exec_mode = vine_task_func_exec_mode_from_int64_t(n);
 			if (func_exec_mode == VINE_TASK_FUNC_EXEC_MODE_INVALID) {
 				debug(D_VINE | D_NOTICE, "invalid func_exec_mode from manager: %s", line);
 				vine_task_delete(task);
@@ -1565,14 +1565,15 @@ static int check_library_startup(struct vine_process *p)
 	}
 
 	vine_task_func_exec_mode_t converted_exec_mode = vine_task_func_exec_mode_from_string(exec_mode);
+	int taskid_int = atoi(taskid);
 
 	if (p->task->provides_library && strcmp(name, p->task->provides_library)) {
 		ok = 0;
 	}
-	if (taskid != p->task->task_id) {
+	if (taskid_int != p->task->task_id) {
 		ok = 0;
 	}
-	if (p->task->exec_mode && converted_exec_mode != p->task->exec_mode) {
+	if (p->task->func_exec_mode && converted_exec_mode != p->task->func_exec_mode) {
 		ok = 0;	
 	}
 	if (response) {

From ccb295139438f10c002f12fefacb455e35ef88e8 Mon Sep 17 00:00:00 2001
From: Thanh Son Phung <tphung@nd.edu>
Date: Thu, 7 Nov 2024 09:33:13 -0500
Subject: [PATCH 4/9] fix bug 2

---
 taskvine/src/worker/vine_worker.c | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/taskvine/src/worker/vine_worker.c b/taskvine/src/worker/vine_worker.c
index 6731a6a225..9e370d847c 100644
--- a/taskvine/src/worker/vine_worker.c
+++ b/taskvine/src/worker/vine_worker.c
@@ -1563,18 +1563,19 @@ static int check_library_startup(struct vine_process *p)
 	if (!name || !taskid || !exec_mode) {
 		ok = 0;	
 	}
+	else {
+		vine_task_func_exec_mode_t converted_exec_mode = vine_task_func_exec_mode_from_string(exec_mode);
+		int taskid_int = atoi(taskid);
 
-	vine_task_func_exec_mode_t converted_exec_mode = vine_task_func_exec_mode_from_string(exec_mode);
-	int taskid_int = atoi(taskid);
-
-	if (p->task->provides_library && strcmp(name, p->task->provides_library)) {
-		ok = 0;
-	}
-	if (taskid_int != p->task->task_id) {
-		ok = 0;
-	}
-	if (p->task->func_exec_mode && converted_exec_mode != p->task->func_exec_mode) {
-		ok = 0;	
+		if (!p->task->provides_library || strcmp(name, p->task->provides_library)) {
+			ok = 0;
+		}
+		if (taskid_int != p->task->task_id) {
+			ok = 0;
+		}
+		if (p->task->func_exec_mode && converted_exec_mode != p->task->func_exec_mode) {
+			ok = 0;	
+		}
 	}
 	if (response) {
 		jx_delete(response);

From 6cf0b8030a85ef359e243b130741ba5fc12f54e5 Mon Sep 17 00:00:00 2001
From: Thanh Son Phung <tphung@nd.edu>
Date: Thu, 7 Nov 2024 09:54:55 -0500
Subject: [PATCH 5/9] fix jx lookup int

---
 taskvine/src/worker/vine_worker.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/taskvine/src/worker/vine_worker.c b/taskvine/src/worker/vine_worker.c
index 9e370d847c..6202d3d72e 100644
--- a/taskvine/src/worker/vine_worker.c
+++ b/taskvine/src/worker/vine_worker.c
@@ -1555,7 +1555,7 @@ static int check_library_startup(struct vine_process *p)
 	struct jx *response = jx_parse_string(buffer);
 
 	const char *name = jx_lookup_string(response, "name");
-	const char *taskid = jx_lookup_string(response, "taskid");
+	int taskid = jx_lookup_integer(response, "taskid");
 	const char *exec_mode = jx_lookup_string(response, "exec_mode");
 
 	int ok = 1;
@@ -1565,12 +1565,11 @@ static int check_library_startup(struct vine_process *p)
 	}
 	else {
 		vine_task_func_exec_mode_t converted_exec_mode = vine_task_func_exec_mode_from_string(exec_mode);
-		int taskid_int = atoi(taskid);
 
 		if (!p->task->provides_library || strcmp(name, p->task->provides_library)) {
 			ok = 0;
 		}
-		if (taskid_int != p->task->task_id) {
+		if (taskid != p->task->task_id) {
 			ok = 0;
 		}
 		if (p->task->func_exec_mode && converted_exec_mode != p->task->func_exec_mode) {

From 109ae1c716b039cfbdcbd5cb3adcbce467eb7155 Mon Sep 17 00:00:00 2001
From: Thanh Son Phung <tphung@nd.edu>
Date: Thu, 7 Nov 2024 09:55:30 -0500
Subject: [PATCH 6/9] format code

---
 taskvine/src/manager/vine_schedule.c | 10 ++++----
 taskvine/src/manager/vine_task.c     | 36 +++++++++++++++-------------
 taskvine/src/worker/vine_worker.c    |  9 ++++---
 3 files changed, 28 insertions(+), 27 deletions(-)

diff --git a/taskvine/src/manager/vine_schedule.c b/taskvine/src/manager/vine_schedule.c
index 7975e8964a..c860f27798 100644
--- a/taskvine/src/manager/vine_schedule.c
+++ b/taskvine/src/manager/vine_schedule.c
@@ -204,11 +204,11 @@ int check_worker_against_task(struct vine_manager *q, struct vine_worker_info *w
 		return 0;
 	}
 
-        /* Check if the library and the worker have the same library protocol version. */
-        if (t->provides_library && (w->library_protocol_version != VINE_LIBRARY_PROTOCOL_VERSION)) {
-                debug(D_VINE, "Worker %s can't run library with id %d due to mismatched library protocol version.", w->workerid, t->task_id);
-                return 0;
-        }
+	/* Check if the library and the worker have the same library protocol version. */
+	if (t->provides_library && (w->library_protocol_version != VINE_LIBRARY_PROTOCOL_VERSION)) {
+		debug(D_VINE, "Worker %s can't run library with id %d due to mismatched library protocol version.", w->workerid, t->task_id);
+		return 0;
+	}
 
 	/* Compute the resources to allocate to this task. */
 	struct rmsummary *l = vine_manager_choose_resources_for_task(q, w, t);
diff --git a/taskvine/src/manager/vine_task.c b/taskvine/src/manager/vine_task.c
index d5f10230ed..c9496bec69 100644
--- a/taskvine/src/manager/vine_task.c
+++ b/taskvine/src/manager/vine_task.c
@@ -328,7 +328,7 @@ void vine_task_set_function_exec_mode(struct vine_task *t, vine_task_func_exec_m
 void vine_task_set_function_exec_mode_from_string(struct vine_task *t, const char *exec_mode)
 {
 	if (exec_mode && t->provides_library) {
-                t->func_exec_mode = vine_task_func_exec_mode_from_string(exec_mode);
+		t->func_exec_mode = vine_task_func_exec_mode_from_string(exec_mode);
 	}
 }
 
@@ -1004,24 +1004,26 @@ char *vine_task_to_json(struct vine_task *t)
 
 /* Converts an int64_t to a valid vine_task_func_exec_mode_t.
  * Returns VINE_TASK_FUNC_EXEC_MODE_INVALID if there's no valid mode for the integer. */
-vine_task_func_exec_mode_t vine_task_func_exec_mode_from_int64_t(int64_t n) {
-        if (n == 1) {
-                return VINE_TASK_FUNC_EXEC_MODE_DIRECT;
-        }
-        if (n == 2) {
-                return VINE_TASK_FUNC_EXEC_MODE_FORK;
-        }
-        return VINE_TASK_FUNC_EXEC_MODE_INVALID;
+vine_task_func_exec_mode_t vine_task_func_exec_mode_from_int64_t(int64_t n)
+{
+	if (n == 1) {
+		return VINE_TASK_FUNC_EXEC_MODE_DIRECT;
+	}
+	if (n == 2) {
+		return VINE_TASK_FUNC_EXEC_MODE_FORK;
+	}
+	return VINE_TASK_FUNC_EXEC_MODE_INVALID;
 }
 
 /* Converts a string to a valid vine_task_func_exec_mode_t.
  * Returns VINE_TASK_FUNC_EXEC_MODE_INVALID if there's no valid mode for the string. */
-vine_task_func_exec_mode_t vine_task_func_exec_mode_from_string(const char *exec_mode) {
-        if (!strncmp(exec_mode, "direct", strlen("direct"))) {
-                return VINE_TASK_FUNC_EXEC_MODE_DIRECT;
-        }
-        if (!strncmp(exec_mode, "fork", strlen("fork"))) {
-                return VINE_TASK_FUNC_EXEC_MODE_FORK;
-        }
-        return VINE_TASK_FUNC_EXEC_MODE_INVALID;
+vine_task_func_exec_mode_t vine_task_func_exec_mode_from_string(const char *exec_mode)
+{
+	if (!strncmp(exec_mode, "direct", strlen("direct"))) {
+		return VINE_TASK_FUNC_EXEC_MODE_DIRECT;
+	}
+	if (!strncmp(exec_mode, "fork", strlen("fork"))) {
+		return VINE_TASK_FUNC_EXEC_MODE_FORK;
+	}
+	return VINE_TASK_FUNC_EXEC_MODE_INVALID;
 }
diff --git a/taskvine/src/worker/vine_worker.c b/taskvine/src/worker/vine_worker.c
index 6202d3d72e..f9ed5a6f59 100644
--- a/taskvine/src/worker/vine_worker.c
+++ b/taskvine/src/worker/vine_worker.c
@@ -1559,11 +1559,10 @@ static int check_library_startup(struct vine_process *p)
 	const char *exec_mode = jx_lookup_string(response, "exec_mode");
 
 	int ok = 1;
-	
+
 	if (!name || !taskid || !exec_mode) {
-		ok = 0;	
-	}
-	else {
+		ok = 0;
+	} else {
 		vine_task_func_exec_mode_t converted_exec_mode = vine_task_func_exec_mode_from_string(exec_mode);
 
 		if (!p->task->provides_library || strcmp(name, p->task->provides_library)) {
@@ -1573,7 +1572,7 @@ static int check_library_startup(struct vine_process *p)
 			ok = 0;
 		}
 		if (p->task->func_exec_mode && converted_exec_mode != p->task->func_exec_mode) {
-			ok = 0;	
+			ok = 0;
 		}
 	}
 	if (response) {

From c470ee33dd238fb9b931bfa57ec07863033c83cd Mon Sep 17 00:00:00 2001
From: Thanh Son Phung <tphung@nd.edu>
Date: Thu, 7 Nov 2024 10:15:24 -0500
Subject: [PATCH 7/9] add doc

---
 doc/manuals/taskvine/index.md | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/doc/manuals/taskvine/index.md b/doc/manuals/taskvine/index.md
index 2c7ed24335..655eb88d4d 100644
--- a/doc/manuals/taskvine/index.md
+++ b/doc/manuals/taskvine/index.md
@@ -2815,13 +2815,24 @@ The `compute` call above may receive the following keyword arguments:
 | resources\_mode | [Automatic resource management](#automatic-resource-management) to use, e.g., "fixed", "max", or "max throughput"| 
 | task\_mode | Mode to execute individual tasks, such as [function calls](#serverless-computing). to use, e.g., "tasks", or "function-calls"|
 
+## Appendix for Developers
 
+### Library - Worker Communication Patterns
 
-### Further Information
+This subsection describes the communication patterns between a library and a worker, agnostic of programming languages a library is implemented in.
+
+Upon library startup, it should send to its worker a json object as a byte stream.
+The json object should have the following keys and associated values' types: `{"name": type-string, "taskid": type-int, "exec\_mode": type-string}`.
+`"name"` should be the name of the library.
+`"taskid"` should be the library' taskid as assigned by a taskvine manager.
+`"exec\_mode"` should be the function execution mode of the library.
+A worker upon receiving a proper library startup message should check all keys against what it knows about the library, and mark the library as ready to receive function calls if the library passes the worker's startup check.
+
+## Further Information
 
 For more information, please see [Getting Help](../help.md) or visit the [Cooperative Computing Lab](http://ccl.cse.nd.edu) website.
 
-### Copyright
+## Copyright
 
 CCTools is Copyright (C) 2022 The University of Notre Dame. This software is distributed under the GNU General Public License Version 2. See the file COPYING for
 details.

From 41fc36351e445fcaf1f6004a4c2dbaf6ff23c7ea Mon Sep 17 00:00:00 2001
From: Thanh Son Phung <tphung@nd.edu>
Date: Mon, 11 Nov 2024 15:15:49 -0500
Subject: [PATCH 8/9] remove conversion from int

---
 taskvine/src/manager/vine_task.c  | 13 -------------
 taskvine/src/manager/vine_task.h  |  1 -
 taskvine/src/worker/vine_worker.c |  2 +-
 3 files changed, 1 insertion(+), 15 deletions(-)

diff --git a/taskvine/src/manager/vine_task.c b/taskvine/src/manager/vine_task.c
index c9496bec69..aaae1d279f 100644
--- a/taskvine/src/manager/vine_task.c
+++ b/taskvine/src/manager/vine_task.c
@@ -1002,19 +1002,6 @@ char *vine_task_to_json(struct vine_task *t)
 	return json;
 }
 
-/* Converts an int64_t to a valid vine_task_func_exec_mode_t.
- * Returns VINE_TASK_FUNC_EXEC_MODE_INVALID if there's no valid mode for the integer. */
-vine_task_func_exec_mode_t vine_task_func_exec_mode_from_int64_t(int64_t n)
-{
-	if (n == 1) {
-		return VINE_TASK_FUNC_EXEC_MODE_DIRECT;
-	}
-	if (n == 2) {
-		return VINE_TASK_FUNC_EXEC_MODE_FORK;
-	}
-	return VINE_TASK_FUNC_EXEC_MODE_INVALID;
-}
-
 /* Converts a string to a valid vine_task_func_exec_mode_t.
  * Returns VINE_TASK_FUNC_EXEC_MODE_INVALID if there's no valid mode for the string. */
 vine_task_func_exec_mode_t vine_task_func_exec_mode_from_string(const char *exec_mode)
diff --git a/taskvine/src/manager/vine_task.h b/taskvine/src/manager/vine_task.h
index 13f56bf4d4..ec6889c096 100644
--- a/taskvine/src/manager/vine_task.h
+++ b/taskvine/src/manager/vine_task.h
@@ -165,7 +165,6 @@ const char *vine_task_state_to_string( vine_task_state_t task_state );
 struct jx * vine_task_to_jx( struct vine_manager *q, struct vine_task *t );
 char * vine_task_to_json(struct vine_task *t);
 
-vine_task_func_exec_mode_t vine_task_func_exec_mode_from_int64_t(int64_t n);
 vine_task_func_exec_mode_t vine_task_func_exec_mode_from_string(const char *exec_mode);
 
 
diff --git a/taskvine/src/worker/vine_worker.c b/taskvine/src/worker/vine_worker.c
index f9ed5a6f59..191d55feeb 100644
--- a/taskvine/src/worker/vine_worker.c
+++ b/taskvine/src/worker/vine_worker.c
@@ -867,7 +867,7 @@ static struct vine_task *do_task_body(struct link *manager, int task_id, time_t
 			/* Also set the total number determined by the manager. */
 			task->function_slots_total = n;
 		} else if (sscanf(line, "func_exec_mode %" PRId64, &n) == 1) {
-			vine_task_func_exec_mode_t func_exec_mode = vine_task_func_exec_mode_from_int64_t(n);
+			vine_task_func_exec_mode_t func_exec_mode = n;
 			if (func_exec_mode == VINE_TASK_FUNC_EXEC_MODE_INVALID) {
 				debug(D_VINE | D_NOTICE, "invalid func_exec_mode from manager: %s", line);
 				vine_task_delete(task);

From 19035dcfbfa6a4d375fdfe744dac1c2dafe7400f Mon Sep 17 00:00:00 2001
From: Thanh Son Phung <tphung@nd.edu>
Date: Thu, 21 Nov 2024 10:07:01 -0500
Subject: [PATCH 9/9] remove library version

---
 taskvine/src/manager/vine_manager.c     | 7 ++-----
 taskvine/src/manager/vine_protocol.h    | 2 --
 taskvine/src/manager/vine_schedule.c    | 7 -------
 taskvine/src/manager/vine_worker_info.h | 3 ---
 taskvine/src/worker/vine_worker.c       | 3 +--
 5 files changed, 3 insertions(+), 19 deletions(-)

diff --git a/taskvine/src/manager/vine_manager.c b/taskvine/src/manager/vine_manager.c
index 190e6c9639..946d1132f7 100644
--- a/taskvine/src/manager/vine_manager.c
+++ b/taskvine/src/manager/vine_manager.c
@@ -1461,10 +1461,9 @@ static vine_msg_code_t handle_taskvine(struct vine_manager *q, struct vine_worke
 {
 	char items[4][VINE_LINE_MAX];
 	int worker_protocol;
-	int worker_library_protocol;
 
-	int n = sscanf(line, "taskvine %d %d %s %s %s %s", &worker_protocol, &worker_library_protocol, items[0], items[1], items[2], items[3]);
-	if (n != 6)
+	int n = sscanf(line, "taskvine %d %s %s %s %s", &worker_protocol, items[0], items[1], items[2], items[3]);
+	if (n != 5)
 		return VINE_MSG_FAILURE;
 
 	if (worker_protocol != VINE_PROTOCOL_VERSION) {
@@ -1473,8 +1472,6 @@ static vine_msg_code_t handle_taskvine(struct vine_manager *q, struct vine_worke
 		return VINE_MSG_FAILURE;
 	}
 
-	w->library_protocol_version = worker_library_protocol;
-
 	if (w->hostname)
 		free(w->hostname);
 	if (w->os)
diff --git a/taskvine/src/manager/vine_protocol.h b/taskvine/src/manager/vine_protocol.h
index d32c495d1f..0fe03196cf 100644
--- a/taskvine/src/manager/vine_protocol.h
+++ b/taskvine/src/manager/vine_protocol.h
@@ -15,8 +15,6 @@ worker, and catalog, but should not be visible to the public user API.
 
 #define VINE_PROTOCOL_VERSION 12
 
-#define VINE_LIBRARY_PROTOCOL_VERSION 1
-
 #define VINE_LINE_MAX 4096       /**< Maximum length of a vine message line. */
 
 #endif
diff --git a/taskvine/src/manager/vine_schedule.c b/taskvine/src/manager/vine_schedule.c
index c860f27798..1127e1e636 100644
--- a/taskvine/src/manager/vine_schedule.c
+++ b/taskvine/src/manager/vine_schedule.c
@@ -10,7 +10,6 @@ See the file COPYING for details.
 #include "vine_file.h"
 #include "vine_file_replica.h"
 #include "vine_mount.h"
-#include "vine_protocol.h"
 
 #include "debug.h"
 #include "hash_table.h"
@@ -204,12 +203,6 @@ int check_worker_against_task(struct vine_manager *q, struct vine_worker_info *w
 		return 0;
 	}
 
-	/* Check if the library and the worker have the same library protocol version. */
-	if (t->provides_library && (w->library_protocol_version != VINE_LIBRARY_PROTOCOL_VERSION)) {
-		debug(D_VINE, "Worker %s can't run library with id %d due to mismatched library protocol version.", w->workerid, t->task_id);
-		return 0;
-	}
-
 	/* Compute the resources to allocate to this task. */
 	struct rmsummary *l = vine_manager_choose_resources_for_task(q, w, t);
 
diff --git a/taskvine/src/manager/vine_worker_info.h b/taskvine/src/manager/vine_worker_info.h
index d5c9dc7c7d..c52fa91103 100644
--- a/taskvine/src/manager/vine_worker_info.h
+++ b/taskvine/src/manager/vine_worker_info.h
@@ -28,9 +28,6 @@ struct vine_worker_info {
 	/* Connection to the worker or other client. */
 	struct link *link;
 
-        /* Library protocol version of this worker. */
-        int library_protocol_version;
-
 	/* Static properties reported by worker when it connects. */
 	char *hostname;
 	char *os;
diff --git a/taskvine/src/worker/vine_worker.c b/taskvine/src/worker/vine_worker.c
index 191d55feeb..273b5cd4b6 100644
--- a/taskvine/src/worker/vine_worker.c
+++ b/taskvine/src/worker/vine_worker.c
@@ -564,9 +564,8 @@ static void report_worker_ready(struct link *manager)
 	}
 
 	send_async_message(manager,
-			"taskvine %d %d %s %s %s %d.%d.%d\n",
+			"taskvine %d %s %s %s %d.%d.%d\n",
 			VINE_PROTOCOL_VERSION,
-			VINE_LIBRARY_PROTOCOL_VERSION,
 			hostname,
 			options->os_name,
 			options->arch_name,