hi all, During kernel code analysis i came across line drivers/net/loopback.c:96:#ifndef LOOPBACK_MUST_CHECKSUM. So i decided to check whether this symbol has been defined i nkernel or not but got no searching line in whole kernel code. Also there are many symbols in this way are implemented in kernel code that checks whether symbol has defined then execute f ollowing statements. where can i find these symbol definitions? regards, linux_lover __________________________________ Do you Yahoo!? Yahoo! Mail - 250MB free storage. Do more. Manage less. http://info.mail.yahoo.com/mail_250 -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/