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-rw-r--r--man2/mremap.233
1 files changed, 19 insertions, 14 deletions
diff --git a/man2/mremap.2 b/man2/mremap.2
index f2b2b98..aa635dd 100644
--- a/man2/mremap.2
+++ b/man2/mremap.2
@@ -8,7 +8,7 @@
.\" Update for Linux 1.3.87 and later
.\" 2005-10-11 mtk: Added NOTES for MREMAP_FIXED; revised EINVAL text.
.\"
-.TH mremap 2 2023-03-30 "Linux man-pages 6.05.01"
+.TH mremap 2 2024-01-16 "Linux man-pages 6.7"
.SH NAME
mremap \- remap a virtual memory address
.SH LIBRARY
@@ -18,7 +18,7 @@ Standard C library
.nf
.BR "#define _GNU_SOURCE" " /* See feature_test_macros(7) */"
.B #include <sys/mman.h>
-.PP
+.P
.BI "void *mremap(void " old_address [. old_size "], size_t " old_size ,
.BI " size_t " new_size ", int " flags ", ... /* void *" new_address " */);"
.fi
@@ -27,7 +27,7 @@ Standard C library
expands (or shrinks) an existing memory mapping, potentially
moving it at the same time (controlled by the \fIflags\fP argument and
the available virtual address space).
-.PP
+.P
\fIold_address\fP is the old address of the virtual memory block that you
want to expand (or shrink).
Note that \fIold_address\fP has to be page
@@ -41,11 +41,13 @@ An optional fifth argument,
may be provided; see the description of
.B MREMAP_FIXED
below.
-.PP
+.P
If the value of \fIold_size\fP is zero, and \fIold_address\fP refers to
-a shareable mapping (see
-.BR mmap (2)
-.BR MAP_SHARED ),
+a shareable mapping
+(see the description of
+.B MAP_SHARED
+in
+.BR mmap (2)),
then
.BR mremap ()
will create a new mapping of the same pages.
@@ -57,7 +59,7 @@ below.
If a new mapping is requested via this method, then the
.B MREMAP_MAYMOVE
flag must also be specified.
-.PP
+.P
The \fIflags\fP bit-mask argument may be 0, or include the following flags:
.TP
.B MREMAP_MAYMOVE
@@ -131,7 +133,7 @@ flag may be used to atomically move a mapping while leaving the source
mapped.
See NOTES for some possible applications of
.BR MREMAP_DONTUNMAP .
-.PP
+.P
If the memory segment specified by
.I old_address
and
@@ -248,7 +250,7 @@ Linux.
.\" 4.2BSD had a (never actually implemented)
.\" .BR mremap (2)
.\" call with completely different semantics.
-.\" .PP
+.\" .P
Prior to glibc 2.4, glibc did not expose the definition of
.BR MREMAP_FIXED ,
and the prototype for
@@ -262,7 +264,7 @@ changes the
mapping between virtual addresses and memory pages.
This can be used to implement a very efficient
.BR realloc (3).
-.PP
+.P
In Linux, memory is divided into pages.
A process has (one or)
several linear virtual memory segments.
@@ -276,7 +278,7 @@ if the memory is accessed incorrectly (e.g.,
writing to a read-only segment).
Accessing virtual memory outside of the
segments will also cause a segmentation violation.
-.PP
+.P
If
.BR mremap ()
is used to move or expand an area locked with
@@ -321,7 +323,10 @@ if
was zero and the mapping referred to by
.I old_address
was a private mapping
-.RB ( mmap "(2) " MAP_PRIVATE ),
+(see the description of
+.B MAP_PRIVATE
+in
+.BR mmap (2)),
.BR mremap ()
created a new private mapping unrelated to the original mapping.
This behavior was unintended
@@ -344,7 +349,7 @@ in this scenario.
.BR sbrk (2),
.BR malloc (3),
.BR realloc (3)
-.PP
+.P
Your favorite text book on operating systems
for more information on paged memory
(e.g., \fIModern Operating Systems\fP by Andrew S.\& Tanenbaum,