how to save a bytea value into a file?

Hello PostgreSQL members：

I'm a user of PostgreSQL. Now I have a question when using it.
When I want to save a bytea value into a file, what should I do？
Is there any function dealing with that in PostgreSQL? (like lo_export() to
deal with the large-object) (# I didn't find any....)

Sorry for interrupting you.
Thanks anyway.

Best regards
Fan Lijing
2011-10-09

Regards
Fan Lijing
--------------------------------------------------------
Oversea Business Department,
Jiangsu Fujitsu Telecommunications Technology Co.,Ltd.(JFTT) No.118, Dengwei
Rd.,Suzhou, P.R. China
Postcode: 215011
PHONE #86-512-68250097-8506 / COINS : 7991-8506
FAX   #86-512-68250045 / COINS FAX :
Mail  #fanlijing@cn.fujitsu.com
--------------------------------------------------------