Using newlib in simulators

[Rosière mathieu]

Hi,

I have seen a subject on how using newlib in a simulator.
In my platform : i have a bridge between the simulator (in which runs a
executable compiling with newlib) and the Os (Linux)
In the function "open", i have a problem using the flags :

for linux the flags are :
0x001 -> WRONLY
0x040 -> O_CREAT
0x200 -> O_TRUNC

For newlib the same flags are :
(file newlib/libc/include/sys/fcntl.h)

0x001 -> WRONLY
0x200 -> O_CREAT
0x400 -> O_TRUNC

Is it normal (is this model for another linux distribution than mine)?
Can the file ../sys/fcntl.h be modified without indesirable effects? 

Regards