+++ /dev/null
-.\" Copyright (C) 1999 Andries Brouwer (aeb@cwi.nl)
-.\"
-.\" %%%LICENSE_START(VERBATIM)
-.\" Permission is granted to make and distribute verbatim copies of this
-.\" manual provided the copyright notice and this permission notice are
-.\" preserved on all copies.
-.\"
-.\" Permission is granted to copy and distribute modified versions of this
-.\" manual under the conditions for verbatim copying, provided that the
-.\" entire resulting derived work is distributed under the terms of a
-.\" permission notice identical to this one.
-.\"
-.\" Since the Linux kernel and libraries are constantly changing, this
-.\" manual page may be incorrect or out-of-date. The author(s) assume no
-.\" responsibility for errors or omissions, or for damages resulting from
-.\" the use of the information contained herein. The author(s) may not
-.\" have taken the same level of care in the production of this manual,
-.\" which is licensed free of charge, as they might when working
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%LICENSE_END
-.\"
-.\" Rewritten old page, 990824, aeb@cwi.nl
-.\" 2004-12-14, mtk, added discussion of resolved_path == NULL
-.\"
-.TH REALPATH 3 2014-10-02 "" "Linux Programmer's Manual"
-.SH NAME
-realpath \- return the canonicalized absolute pathname
-.SH SYNOPSIS
-.nf
-.B #include <limits.h>
-.B #include <stdlib.h>
-.sp
-.BI "char *realpath(const char *" path ", char *" resolved_path );
-.fi
-.sp
-.in -4n
-Feature Test Macro Requirements for glibc (see
-.BR feature_test_macros (7)):
-.in
-.sp
-.BR realpath ():
-.ad l
-.RS 4
-_BSD_SOURCE || _XOPEN_SOURCE\ >=\ 500 ||
-_XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED
-.RE
-.ad
-.SH DESCRIPTION
-.BR realpath ()
-expands all symbolic links and resolves references
-to
-.IR "/./" ", " "/../"
-and extra \(aq/\(aq
-characters in the null-terminated string named by
-.I path
-to produce a canonicalized absolute pathname.
-The resulting pathname is stored as a null-terminated string,
-up to a maximum of
-.B PATH_MAX
-bytes,
-in the buffer pointed to by
-.IR resolved_path .
-The resulting path will have no symbolic link,
-.I "/./"
-or
-.I "/../"
-components.
-
-If
-.I resolved_path
-is specified as NULL, then
-.BR realpath ()
-uses
-.BR malloc (3)
-to allocate a buffer of up to
-.B PATH_MAX
-bytes to hold the resolved pathname,
-and returns a pointer to this buffer.
-The caller should deallocate this buffer using
-.BR free (3).
-.\" Even if we use resolved_path == NULL, then realpath() will still
-.\" return ENAMETOOLONG if the resolved pathname would exceed PATH_MAX
-.\" bytes -- MTK, Dec 04
-.\" .SH HISTORY
-.\" The
-.\" .BR realpath ()
-.\" function first appeared in 4.4BSD, contributed by Jan-Simon Pendry.
-.SH RETURN VALUE
-If there is no error,
-.BR realpath ()
-returns a pointer to the
-.IR resolved_path .
-
-Otherwise, it returns NULL, the contents
-of the array
-.I resolved_path
-are undefined, and
-.I errno
-is set to indicate the error.
-.SH ERRORS
-.TP
-.B EACCES
-Read or search permission was denied for a component of the path prefix.
-.TP
-.B EINVAL
-.I path
-is NULL.
-.\" (In libc5 this would just cause a segfault.)
-(In glibc versions before 2.3,
-this error is also returned if
-.IR resolved_path
-is NULL.)
-.TP
-.B EIO
-An I/O error occurred while reading from the filesystem.
-.TP
-.B ELOOP
-Too many symbolic links were encountered in translating the pathname.
-.TP
-.B ENAMETOOLONG
-A component of a pathname exceeded
-.B NAME_MAX
-characters, or an entire pathname exceeded
-.B PATH_MAX
-characters.
-.TP
-.B ENOENT
-The named file does not exist.
-.TP
-.B ENOTDIR
-A component of the path prefix is not a directory.
-.SH CONFORMING TO
-4.4BSD, POSIX.1-2001.
-
-POSIX.1-2001 says that the behavior if
-.I resolved_path
-is NULL is implementation-defined.
-POSIX.1-2008 specifies the behavior described in this page.
-.SH NOTES
-In 4.4BSD and Solaris, the limit on the pathname length is
-.B MAXPATHLEN
-(found in \fI<sys/param.h>\fP).
-SUSv2 prescribes
-.B PATH_MAX
-and
-.BR NAME_MAX ,
-as found in \fI<limits.h>\fP or provided by the
-.BR pathconf (3)
-function.
-A typical source fragment would be
-.LP
-.in +4n
-.nf
-#ifdef PATH_MAX
- path_max = PATH_MAX;
-#else
- path_max = pathconf(path, _PC_PATH_MAX);
- if (path_max <= 0)
- path_max = 4096;
-#endif
-.fi
-.in
-.LP
-(But see the BUGS section.)
-.LP
-.\" 2012-05-05, According to Casper Dik, the statement about
-.\" Solaris was not true at least as far back as 1997, and
-.\" may never have been true.
-.\"
-.\" The 4.4BSD, Linux and SUSv2 versions always return an absolute
-.\" pathname.
-.\" Solaris may return a relative pathname when the
-.\" .I path
-.\" argument is relative.
-.\" The prototype of
-.\" .BR realpath ()
-.\" is given in \fI<unistd.h>\fP in libc4 and libc5,
-.\" but in \fI<stdlib.h>\fP everywhere else.
-.SS GNU extensions
-If the call fails with either
-.BR EACCES
-or
-.BR ENOENT
-and
-.I resolved_path
-is not NULL, then the prefix of
-.I path
-that is not readable or does not exist is returned in
-.IR resolved_path .
-.SH BUGS
-The POSIX.1-2001 standard version of this function is broken by design,
-since it is impossible to determine a suitable size for the output buffer,
-.IR resolved_path .
-According to POSIX.1-2001 a buffer of size
-.B PATH_MAX
-suffices, but
-.B PATH_MAX
-need not be a defined constant, and may have to be obtained using
-.BR pathconf (3).
-And asking
-.BR pathconf (3)
-does not really help, since, on the one hand POSIX warns that
-the result of
-.BR pathconf (3)
-may be huge and unsuitable for mallocing memory,
-and on the other hand
-.BR pathconf (3)
-may return \-1 to signify that
-.B PATH_MAX
-is not bounded.
-The
-.I "resolved_path\ ==\ NULL"
-feature, not standardized in POSIX.1-2001,
-but standardized in POSIX.1-2008, allows this design problem to be avoided.
-.\" .LP
-.\" The libc4 and libc5 implementation contained a buffer overflow
-.\" (fixed in libc-5.4.13).
-.\" Thus, set-user-ID programs like
-.\" .BR mount (8)
-.\" needed a private version.
-.SH SEE ALSO
-.BR realpath (1),
-.BR readlink (2),
-.BR canonicalize_file_name (3),
-.BR getcwd (3),
-.BR pathconf (3),
-.BR sysconf (3)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
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