xnu-4903.270.47.tar.gz

[apple/xnu.git] / bsd / man / man2 / mmap.2

diff --git a/bsd/man/man2/mmap.2 b/bsd/man/man2/mmap.2
index b55d054e109830005a47351dc028a8662dd01f27..9cbe1aa2a3aee083ec86096ad14aaa3a360d0597 100644 (file)
--- a/bsd/man/man2/mmap.2
+++ b/bsd/man/man2/mmap.2
@@ -126,6 +126,9 @@ argument by
 .Em or Ns 'ing
 the following values:
 .Bl -tag -width MAP_HASSEMAPHORE
+.It Dv MAP_ANONYMOUS
+Synonym for
+.Dv MAP_ANON.
 .It Dv MAP_ANON
 Map anonymous memory not associated with any specific file.
 The
@@ -141,22 +144,14 @@ to
 .Nm mmap
 are:
 .Pp
-VM_FLAGS_PURGABLE      to create Mach purgable (i.e. volatile) memory
+VM_FLAGS_PURGABLE      to create Mach purgable (i.e. volatile) memory.
 .Pp
-VM_MAKE_TAG(tag)       to associate an 8-bit tag with the region
+VM_MAKE_TAG(tag)       to associate an 8-bit tag with the region.
 .br
 <mach/vm_statistics.h> defines some preset tags (with a VM_MEMORY_ prefix).
 Users are encouraged to use tags between 240 and 255.
 Tags are used by tools such as vmmap(1) to help identify specific memory regions.
 .Pp
-VM_FLAGS_SUPERPAGE_SIZE_*      to use superpages for the allocation. 
-See <mach/vm_statistics.h> for supported architectures and sizes (or use
-VM_FLAGS_SUPERPAGE_SIZE_ANY to have the kernel choose a size).
-The specified size must be divisible by the superpage size (except for
-VM_FLAGS_SUPERPAGE_SIZE_ANY), and if you use MAP_FIXED, the specified address
-must be properly aligned. If the system cannot satisfy the request with superpages,
-the call will fail. Note that currently, superpages are always wired and not
-inherited by children of the process.
 .It Dv MAP_FILE
 Mapped from a regular file.  (This is
 the default mapping type, and need not be specified.)
@@ -265,7 +260,9 @@ does not include either MAP_PRIVATE or MAP_SHARED.
 The
 .Fa len
 argument
-was negative.
+was negative or zero. Historically, the system call would not return an error if the argument was zero. 
+See other potential additional restrictions in the 
+COMPATIBILITY section below. 
 .It Bq Er EINVAL
 The
 .Fa offset
@@ -314,7 +311,7 @@ The
 parameter must specify either MAP_PRIVATE or MAP_SHARED.
 .It
 The
-.Fa size
+.Fa len
 parameter must not be 0.
 .It
 The