Include directories

Include directories

[Sertaç Olgunsoylu]

Hi,
While I was doing some reading on system calls, I did a search for
"syscalls.h" to find the header file in LXR. The search results puzzled me.
There is a dozen of "syscalls.h" files coming from directories under
"arch/_arch_name_/include/asm". These are ok, they are architecture
specific definitions or something else needed. The question is why do we
have two different "syscalls.h" headers under both /include/linux and
/include/asm-generic?

Also, I want to understand that what /include/linux headers are for and
what /include/asm-generic headers are for. How do they differentiate
between each other? What is the logic behind having two separate header
folders? How do they relate to each other?

Thanks
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Include directories

[Cihangir Aktürk]

> Hi,

Hi,

> Also, I want to understand that what /include/linux headers are for and what
> /include/asm-generic?headers are for. How do they?differentiate between each
> other??What is the logic behind having two separate header folders? How do
> they relate to each other?

AFAIK, headers found in /include/asm-generic directory is for architechture
independent (probably shared across architectures) code. Most likely you do
not need to include these headers directly, instead we include these headers
indirectly via architecthure dependent headers.

OTOH, /include/linux directory is for generic header files to define interfaces
between components of the kernel. In most situations, you will find all the
kernel functionalities you need in these headers.

regards, chngr.