Add i86pc to unames detected as x86 (used by Solaris).

[pintos-anon] / doc / userprog.texi

diff --git a/doc/userprog.texi b/doc/userprog.texi
index bb05dfb326b091e48cdeff21f744c73ddd0179f6..b50dc364829edcc186491b875e68e1b4cd470a72 100644 (file)
--- a/doc/userprog.texi
+++ b/doc/userprog.texi
@@ -301,7 +301,7 @@ regardless of what user process or kernel thread is running.  In
 Pintos, kernel virtual memory is mapped one-to-one to physical
 memory, starting at @code{PHYS_BASE}.  That is, virtual address
 @code{PHYS_BASE} accesses physical
 Pintos, kernel virtual memory is mapped one-to-one to physical
 memory, starting at @code{PHYS_BASE}.  That is, virtual address
 @code{PHYS_BASE} accesses physical

-address 0, virtual address @code{PHYS_BASE} + @t{0x1234} access
+address 0, virtual address @code{PHYS_BASE} + @t{0x1234} accesses

 physical address @t{0x1234}, and so on up to the size of the machine's
 physical memory.
 
 physical address @t{0x1234}, and so on up to the size of the machine's
 physical memory.
 


@@ -314,11 +314,6 @@ the running process.  However, even in the kernel, an attempt to
 access memory at an unmapped user virtual address
 will cause a page fault.
 
 access memory at an unmapped user virtual address
 will cause a page fault.
 

-You must handle memory fragmentation gracefully, that is, a process that
-needs @var{N} pages of user virtual memory must not require those pages
-to be contiguous in physical memory (or, equivalently, in kernel virtual
-memory).
-

 @menu
 * Typical Memory Layout::       
 @end menu
 @menu
 * Typical Memory Layout::       
 @end menu


@@ -679,6 +674,12 @@ as explicitly described below.
 
 Each process has an independent set of file descriptors.  File
 descriptors are not inherited by child processes.
 
 Each process has an independent set of file descriptors.  File
 descriptors are not inherited by child processes.

+
+When a single file is opened more than once, whether by a single
+process or different processes, each @code{open} returns a new file
+descriptor.  Different file descriptors for a single file are closed
+independently in separate calls to @code{close} and they do not share
+a file position.

 @end deftypefn
 
 @deftypefn {System Call} int filesize (int @var{fd})
 @end deftypefn
 
 @deftypefn {System Call} int filesize (int @var{fd})