Hello, On 1/20/07, Bob Copeland <me@xxxxxxxxxxxxxxx> wrote:
On 1/19/07, Shakthi Kannan <shakthimaan@xxxxxxxxx> wrote: > Hi, > > On 1/19/07, Ramagudi Naziir <naziirr@xxxxxxxxx> wrote: > > Is there a difference between u32 to __u32 ? > > (I didn't see any in the source). > > __u32 is usually used to refer to variables that interact with user-space. > > /* 9 * __xx is ok: it doesn't pollute the POSIX namespace. Use these > in the 10 * header files exported to user space 11 */ > > http://lxr.linux.no/source/include/asm-i386/types.h#L20 > > > and what are __le16 and __be16 ? > > unsigned short for little endian and big-endian formats. In other words, use __le32 or __be32 if you care about the endianness and it is the same on all platforms, for example if you are reading filesystem blocks from disk. This way you can make sure that you didn't miss any le32_to_cpu() calls by checking with the sparse tool
can you please explain this ? what is le32_to_cpu ?
(this is where bitwise comes in). Otherwise, use u32 or __u32, the latter alone if exported to user space.
can you please explain this too ? what is the difference ? what is a value that is exported to user space ? Thank You naziir
Bob
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