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+.\" Copyright (C) 1994, 1995, Daniel Quinlan <quinlan@yggdrasil.com>
+.\" Copyright (C) 2002-2008, 2017, Michael Kerrisk <mtk.manpages@gmail.com>
+.\" Copyright (C) 2023, Alejandro Colomar <alx@kernel.org>
+.\"
+.\" SPDX-License-Identifier: GPL-3.0-or-later
+.\"
+.TH proc_pid_map_files 5 2024-05-02 "Linux man-pages (unreleased)"
+.SH NAME
+/proc/pid/map_files/ \- memory-mapped files
+.SH DESCRIPTION
+.TP
+.IR /proc/ pid /map_files/ " (since Linux 3.3)"
+.\" commit 640708a2cff7f81e246243b0073c66e6ece7e53e
+This subdirectory contains entries corresponding to memory-mapped
+files (see
+.BR mmap (2)).
+Entries are named by memory region start and end
+address pair (expressed as hexadecimal numbers),
+and are symbolic links to the mapped files themselves.
+Here is an example,
+with the output wrapped and reformatted to fit on an 80-column display:
+.IP
+.in +4n
+.EX
+.RB "#" " ls \-l /proc/self/map_files/"
+lr\-\-\-\-\-\-\-\-. 1 root root 64 Apr 16 21:31
+            3252e00000\-3252e20000 \-> /usr/lib64/ld\-2.15.so
+\&...
+.EE
+.in
+.IP
+Although these entries are present for memory regions that were
+mapped with the
+.B MAP_FILE
+flag, the way anonymous shared memory (regions created with the
+.B MAP_ANON | MAP_SHARED
+flags)
+is implemented in Linux
+means that such regions also appear on this directory.
+Here is an example where the target file is the deleted
+.I /dev/zero
+one:
+.IP
+.in +4n
+.EX
+lrw\-\-\-\-\-\-\-. 1 root root 64 Apr 16 21:33
+            7fc075d2f000\-7fc075e6f000 \-> /dev/zero (deleted)
+.EE
+.in
+.IP
+Permission to access this file is governed by a ptrace access mode
+.B PTRACE_MODE_READ_FSCREDS
+check; see
+.BR ptrace (2).
+.IP
+Until Linux 4.3,
+.\" commit bdb4d100afe9818aebd1d98ced575c5ef143456c
+this directory appeared only if the
+.B CONFIG_CHECKPOINT_RESTORE
+kernel configuration option was enabled.
+.IP
+Capabilities are required to read the contents of the symbolic links in
+this directory: before Linux 5.9, the reading process requires
+.B CAP_SYS_ADMIN
+in the initial user namespace;
+since Linux 5.9, the reading process must have either
+.B CAP_SYS_ADMIN
+or
+.B CAP_CHECKPOINT_RESTORE
+in the initial (i.e. root) user namespace.
+.SH SEE ALSO
+.BR proc (5)