From: Ben Pfaff Date: Tue, 20 Dec 2005 23:24:52 +0000 (+0000) Subject: Clarify that struct intr_frame is on the kernel stack. X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1044569eb62fa925bde405cd84a47576db415818;p=pintos-anon Clarify that struct intr_frame is on the kernel stack. Thanks to "Kevin Hart" for the question. --- diff --git a/doc/userprog.texi b/doc/userprog.texi index 92959ec..6593260 100644 --- a/doc/userprog.texi +++ b/doc/userprog.texi @@ -1045,8 +1045,9 @@ Thus, when the system call handler @func{syscall_handler} gets control, the system call number is in the 32-bit word at the caller's stack pointer, the first argument is in the 32-bit word at the next higher address, and so on. The caller's stack pointer is accessible to -@func{syscall_handler} as the @samp{esp} member of the @code{struct -intr_frame} passed to it. +@func{syscall_handler} as the @samp{esp} member of the +@struct{intr_frame} passed to it. (@struct{intr_frame} is on the kernel +stack.) The 80@var{x}86 convention for function return values is to place them in the @code{EAX} register. System calls that return a value can do