C++ writing unsigned int to a file

k++

k++

k++

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I have looked everywhere and can't for the life of me find exactly what I'm looking for.

I'm trying to write a load of unsigned integers to a binary file, the problem is I can only find how to write characters. That isn't a binary file really, I would like to store just 32-bits for each uint.

ofstream.write() requires a character array, if I typecast my uint to (char*) it reverses the order so the number (in hex) 04004000 is written as 00400040.

How nuts is that.

I'm also having a problem reading these files properly, I have written a Java version of my program which works perfectly except it doesn't support unsigned integers so I'm stuck with 64-bit numbers. I can't seem to load the numbers one at a time using c++

:confused:
 
I have just discovered reinterpret_cast and think I have solved my problem.

Thanks for looking though :)
 
Im pretty sure ostream.write actually takes a const char* with a size of how much to write. You should not use reinterpret_cast to do what your trying to do either. I remember doing something like this ages ago and seem to recall using the ostream.put to write individual characters. Long time since ive done any not .NET c++ :)
 
k++ said:
ofstream.write() requires a character array, if I typecast my uint to (char*) it reverses the order so the number (in hex) 04004000 is written as 00400040.

How nuts is that.
Click to expand...

That'll be because the number is stored in memory with little-endian byte order.
 
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