Symbain的程序主要是用UID标识的，在v9.0后UIDs分为两类，Protected和Unprotected。
UID
Class
Range
Purpose
Protected Range
0
0x00000000 - 0x0FFFFFFF
Development use only
1
0x10000000 - 0x1FFFFFFF
Legacy UID allocations
2
0x20000000 - 0x2FFFFFFF
V9 protected UID allocations
3
0x30000000 - 0x3FFFFFFF
Reserved
4
0x40000000 - 0x4FFFFFFF
Reserved
5
0x50000000 - 0x5FFFFFFF
Reserved
6
0x60000000 - 0x6FFFFFFF
Reserved
7
0x70000000 - 0x7FFFFFFF
Vendor IDs.
Unprotected Range
8
0x80000000 - 0x8FFFFFFF
Reserved
9
0x90000000 - 0x9FFFFFFF
Reserved
A
0xA0000000 - 0xAFFFFFFF
V9 unprotected UID allocations
B
0xB0000000 - 0xBFFFFFFF
Reserved
C
0xC0000000 - 0xCFFFFFFF
Reserved
D
0xD0000000 - 0xDFFFFFFF
Reserved
E
0xE0000000 - 0xEFFFFFFF
Development use only
F
0xF0000000 - 0xFFFFFFFF
Legacy UID compatibility range
如果开发一些Symbian的项目，将来要签名的使用Protected UID，程序必须签名才能安装在真机上。Unprotected可以用来做一些测试、教学程序。
每个应用程序都有3个UID。uid1用于表示Symbian OS平台程序的类型：For EXE uid1 = 0x1000007A； For DLL&APP uid1 = 0x10000079；For ECom Plugin 0x10009D8D。UID2一般都去固定值0x100039CE，我也没有弄清楚具体的作用。UID3标识应用程序。SID的取值和UID3一样。VID一般都取默认的0。UID都在程序的MMP中定义。