FS:[0x1C] 4 NT Environment Pointer
FS:[0x20] 4 NT Process ID (in some windows distributions this field is used as 'DebugContext')
FS:[0x24] 4 NT Current thread ID
FS:[0x28] 4 NT Active RPC Handle
FS:[0x2C] 4 Win9x and NT Linear address of the thread-local storage array
FS:[0x30] 4 NT Linear address of Process Environment Block (PEB)
FS:[0x34] 4 NT Last error number
FS:[0x38] 4 NT Count of owned critical sections