Jose Luis Alarcon wrote:
The operators >> and & are binary operators as opposed to ~ which is a unary operator.--- Tadeusz Andrzej Kadłubowski <yess@hell.org.pl> wrote:On Tue, Dec 03, 2002 at 11:52:03AM -0800, Jose Luis Alarcon wrote:Hi all. I am trying compile a module that contains this line: printk("Device: %d.%d\n", inode->i_rdev >> 8, inode->i_rdev & 0xFF); and the result is that gcc 3.2.1 says that '>>' and '&' are wrong operators for the binary. Why?My guess: i_rdev in inode structure is of type kdev_t, which is defined in include/linux/kdev_t.h and contains one member - unsigned short value. Maybe try shifting/bitwise anding not on the structure, but on that particular member of the structure. Then if inode is a pointer to the inode struct, then it would be something like: printk("Device: %d.%d\n", (inode->i_rdev).value >> 8, (inode->i_rdev) & 0xff); This guess obviously may occur wrong. Please tell, if it worked. -- tadeusz a. kadlubowskiHi Tadeusz, and thanks for your answer. Your proposed line: printk("Device: %d.%d\n", (inode->i_rdev).value >> 8, (inode->i_rdev) & 0xff); gets solve the problem for '>>' but not for '&'. I paste here down the output: chardev.c:91: wrong operators for the binary & Why gcc think that & is a binary?. I suppose Ori Pomerantz use '>>' and '&' like bits level operators.
I would strongly recommend that you find a copy of K&R (or some C language book) and study the bitwise operators and the C types they apply to. Once you understand that, the problem with the line of code you tried should be apparent.
HTH,
Eli
--------------------. "If it ain't broke now,
Eli Carter \ it will be soon." -- crypto-gram
eli.carter(a)inet.com `-------------------------------------------------
--
Kernelnewbies: Help each other learn about the Linux kernel.
Archive: http://mail.nl.linux.org/kernelnewbies/
FAQ: http://kernelnewbies.org/faq/
