how to terminate hang up sender process

Hi all,

I'm using PostgreSQL 9.1.7's replication function for my HA project
and getting trouble when terminate the hangup sender process.

My cluster configuration: Node1(MASTER) Node2(STANDBY)

Execution sequence:
---
 step 1.
 execute pg_basebackup on Node2

 step 2.
 While Node2's pg_basebackup is processing (wal sender was
 created in Node1), turn off the Node2 by power off buton.
---

Problem:
---
the sender process in Node1 for base_backup of Node2(SLAVE)
was hanging up (in about 30 minutes).
---

Question:
---
Is there's a solution to terminate that [wal sender] in Node1 but not
restart or kill (-9) the process?
---

I've tried with replication_timeout=60s (default)

best regards,
Huong DM.