关于系统调用2.6.32

在include/linux/syscalls.h中有如下宏：

SYSCALL_DEFINE1

 ... 

SYSCALL_DEFINE6

如

SYSCALL_DEFINE3(open, const char __user *, filename, int, flags, int, mode)

展开就是sys_open的原型

asmlinkage long sys_open(const char __user *filename,

int flags, int mode);

整个代码：

SYSCALL_DEFINE3(open, const char __user *, filename, int, flags, int, mode)

{

long ret;

if (force_o_largefile())

flags |= O_LARGEFILE;

ret = do_sys_open(AT_FDCWD, filename, flags, mode);

/* avoid REGPARM breakage on x86: */

asmlinkage_protect(3, ret, filename, flags, mode);

return ret;

}

系统调用有几个参数就使用对应的SYSCALL_DEFINEx。