as a followup to an earlier post, this is kind of a nebulous proposal but i want to start collecting examples out of the kernel source tree that demonstrate a lot of the basic or introductory kernel programming concepts. with some of the courseware i deal with, there's typically a perfectly reasonable explanation for numerous introductory concepts and topics, but none of that beats being accompanied by an actual example right out of the source. for example, i can explain in detail how to write a simple, read-only proc file, or i can just point at some terrific examples in the fs/proc directory, such as version.c: === snip header files === static int version_proc_show(struct seq_file *m, void *v) { seq_printf(m, linux_proc_banner, utsname()->sysname, utsname()->release, utsname()->version); return 0; } static int version_proc_open(struct inode *inode, struct file *file) { return single_open(file, version_proc_show, NULL); } static const struct file_operations version_proc_fops = { .open = version_proc_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, }; static int __init proc_version_init(void) { proc_create("version", 0, NULL, &version_proc_fops); return 0; } module_init(proc_version_init); === end version.c === once you see that living, breathing example, what more would you need to know about how to have your module/driver create a simple read-only proc file? as another example, we all know that if your module init() routine runs into an error, it has an obligation to carefully (and, typically, in reverse order) undo everything it's done up to that point. sometimes, that routine is loaded with "goto" stmts. other times, the module author might create a "cleanup" routine that is callable from both the init and exit routines. i'm currently perusing the source for nice, uncluttered examples of exactly that (where the explanation isn't buried under extraneous processing to the point where it's hard to see the relevant code). and the list goes on and on -- there are assuredly all sorts of source files for drivers that can be used as respectable examples of all sorts of *introductory* concepts. i'm also interesting in collecting examples of documentation for basic kernel programming concepts. sometimes, there are excellent examples in the source Documentation/ directory, sometimes not. or there might be high-quality tutorials at places like lwn.net, developerworks, and lots of other places. i'm interested in starting a list of tutorials like that that explain, ideally, a single topic really, really well for the sake of beginners. thoughts? rday -- ======================================================================== Robert P. J. Day Ottawa, Ontario, CANADA http://crashcourse.ca Twitter: http://twitter.com/rpjday LinkedIn: http://ca.linkedin.com/in/rpjday ========================================================================