I want to set a file from read-write to read-only and copy the following code (from Google) to my program, but failed. Anyone can point out what is wrong?

TIA
Ben

*--------------------------------------------
FUNC changeattr
DECLARE INTEGER SetFileAttributes IN kernel32 STRING @,INTEGER @
PRIVATE cFn
cFilename="e:\testingfa\testfile.txt"
#DEFINE FILE_ATTRIBUTE_READONLY 0x1
m=SetFileAttributes(@cFilename,FILE_ATTRIBUTE_READONLY)
RETURN m