Is there a place, other than "use the source, Luke!" where I could learn about how the Linux kernel in particular is structured for the z? I am particularly interested in how an application makes a request to the kernel. I.e. how switching from user mode to kernel mode is accomplished. I am fairly knowledgeable about z/OS internals and the use of SVCs and PC/PT/PR to invoke z/OS supervisor services. Does Linux on z use only SVCs? Just one, or multiple? Does it use the PC instruction?
Why am I curious? Well, I am in general anyway. But I worked long ago with a product called DUO. It allowed applications written for s/370 series DOS to run under MVS. It worked by trapping SVCs and emulating the DOS environment on top of MVS. I was curious if such a thing would be possible with z/Linux applications to run them under z/OS UNIX, somewhat like WINE allows Windows apps to run under Linux/Intel. Why? Because it would be easier than porting the GNU utilities to run on z/OS. Especially seeing as how I don't have a C compiler on z/OS. The only real gotcha that I can see off hand would be the ASCII vs. EBCDIC issue. Then again, I am known to be overly weird (if you follow IBM-MAIN). -- John McKown Maranatha! <>< ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
