* ptx: (coreutils)ptx invocation. Produce permuted indexes.
* pwd: (coreutils)pwd invocation. Print working directory.
* readlink: (coreutils)readlink invocation. Print referent of a symlink.
+* realpath: (coreutils)readpath invocation. Print resolved file names.
* rm: (coreutils)rm invocation. Remove files.
* rmdir: (coreutils)rmdir invocation. Remove empty directories.
* runcon: (coreutils)runcon invocation. Run in specified SELinux CTX.
* Printing text:: echo printf yes
* Conditions:: false true test expr
* Redirection:: tee
-* File name manipulation:: dirname basename pathchk mktemp
+* File name manipulation:: dirname basename pathchk mktemp realpath
* Working context:: pwd stty printenv tty
* User information:: id logname whoami groups users who
* System context:: date arch nproc uname hostname hostid uptime
* dirname invocation:: Strip last file name component
* pathchk invocation:: Check file name validity and portability
* mktemp invocation:: Create temporary file or directory
+* realpath invocation:: Print resolved file names
Working context
@cindex displaying value of a symbolic link
@cindex canonical file name
@cindex canonicalize a file name
-@pindex realpath
@findex realpath
@command{readlink} may work in one of two supported modes:
The @command{readlink} utility first appeared in OpenBSD 2.1.
-There is a @command{realpath} command on some systems
-which operates like @command{readlink} in canonicalize mode.
+The @command{realpath} command without options, operates like
+@command{readlink} in canonicalize mode.
@exitstatus
* dirname invocation:: Strip last file name component.
* pathchk invocation:: Check file name validity and portability.
* mktemp invocation:: Create temporary file or directory.
+* realpath invocation:: Print resolved file names.
@end menu
@end display
+@node realpath invocation
+@section @command{realpath}: Print the resolved file name.
+
+@pindex realpath
+@cindex file names, canonicalization
+@cindex symlinks, resolution
+@cindex canonical file name
+@cindex canonicalize a file name
+@pindex realpath
+@findex realpath
+
+@command{realpath} expands all symbolic links and resolves references to
+@samp{/./}, @samp{/../} and extra @samp{/} characters. By default,
+all but the last component of the specified files must exist. Synopsis:
+
+@example
+realpath [@var{option}]@dots{} @var{file}@dots{}
+@end example
+
+The program accepts the following options. Also see @ref{Common options}.
+
+@table @samp
+
+@item -e
+@itemx --canonicalize-existing
+@opindex -e
+@opindex --canonicalize-existing
+Ensure that all components of the specified file names exist.
+If any component is missing or unavailable, @command{realpath} will output
+a diagnostic unless the @option{-q} option is specified, and exit with a
+nonzero exit code. A trailing slash requires that the name resolve to a
+directory.
+
+@item -m
+@itemx --canonicalize-missing
+@opindex -m
+@opindex --canonicalize-missing
+If any component of a specified file name is missing or unavailable,
+treat it as a directory.
+
+@item -L
+@itemx --logical
+@opindex -L
+@opindex --logical
+Symbolic links are resolved in the specified file names,
+but they are resolved after any subsequent @samp{..} components are processed.
+
+@item -P
+@itemx --physical
+@opindex -P
+@opindex --physical
+Symbolic links are resolved in the specified file names,
+and they are resolved before any subsequent @samp{..} components are processed.
+This is the default mode of operation.
+
+@item -q
+@itemx --quiet
+@opindex -q
+@opindex --quiet
+Suppress diagnostic messages for specified file names.
+
+@item -s
+@itemx --strip
+@itemx --no-symlinks
+@opindex -s
+@opindex --strip
+@opindex --no-symlinks
+Do not resolve symbolic links. Only resolve references to
+@samp{/./}, @samp{/../} and remove extra @samp{/} characters.
+When combined with the @option{-m} option, realpath operates
+only on the file name, and does not touch any actual file.
+
+@item -z
+@itemx --zero
+@opindex -z
+@opindex --zero
+Separate output items with @sc{nul} characters.
+
+@itemx --relative-to=@var{file}
+@opindex --relative-to
+@cindex relpath
+Print the resolved file names relative to the specified file.
+Note this option honors the @option{-m} and @option{-e} options
+pertaining to file existence.
+
+@itemx --relative-base=@var{base}
+@opindex --relative-base
+This option is valid when used with @option{--relative-to}, and will restrict
+the output of @option{--relative-to} so that relative names are output,
+only when @var{file}s are descendants of @var{base}. Otherwise output the
+absolute file name. Note: this option honors the @option{-m} and @option{-e}
+options pertaining to file existence. For example:
+
+@example
+realpath --relative-to=/usr /tmp /usr/bin
+@result{} ../tmp
+@result{} bin
+realpath --relative-base=/usr --relative-to=/usr /tmp /usr/bin
+@result{} /tmp
+@result{} bin
+@end example
+
+@end table
+
+@cindex exit status of @command{realpath}
+Exit status:
+
+@display
+0 if all file names were printed without issue.
+1 otherwise.
+@end display
+
+
@node Working context
@chapter Working context
--- /dev/null
+/* realpath - print the resolved path
+ Copyright (C) 2011-2012 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+/* Written by Pádraig Brady. */
+
+#include <config.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <sys/types.h>
+
+#include "system.h"
+#include "canonicalize.h"
+#include "error.h"
+#include "quote.h"
+
+/* The official name of this program (e.g., no `g' prefix). */
+#define PROGRAM_NAME "realpath"
+
+#define AUTHORS proper_name_utf8 ("Padraig Brady", "P\303\241draig Brady")
+
+enum
+{
+ RELATIVE_TO_OPTION = CHAR_MAX + 1,
+ RELATIVE_BASE_OPTION
+};
+
+static bool verbose = true;
+static bool logical;
+static bool use_nuls;
+static const char *can_relative_to;
+static const char *can_relative_base;
+
+static struct option const longopts[] =
+{
+ {"canonicalize-existing", no_argument, NULL, 'e'},
+ {"canonicalize-missing", no_argument, NULL, 'm'},
+ {"relative-to", required_argument, NULL, RELATIVE_TO_OPTION},
+ {"relative-base", required_argument, NULL, RELATIVE_BASE_OPTION},
+ {"quiet", no_argument, NULL, 'q'},
+ {"strip", no_argument, NULL, 's' /* FIXME: deprecate in 2013 or so */},
+ {"no-symlinks", no_argument, NULL, 's'},
+ {"zero", no_argument, NULL, 'z'},
+ {"logical", no_argument, NULL, 'L'},
+ {"physical", no_argument, NULL, 'P'},
+ {GETOPT_HELP_OPTION_DECL},
+ {GETOPT_VERSION_OPTION_DECL},
+ {NULL, 0, NULL, 0}
+};
+
+void
+usage (int status)
+{
+ if (status != EXIT_SUCCESS)
+ fprintf (stderr, _("Try `%s --help' for more information.\n"),
+ program_name);
+ else
+ {
+ printf (_("Usage: %s [OPTION]... FILE...\n"), program_name);
+ fputs (_("\
+Print the resolved absolute file name;\n\
+all but the last component must exist\n\
+\n\
+"), stdout);
+ fputs (_("\
+ -e, --canonicalize-existing all components of the path must exist\n\
+ -m, --canonicalize-missing no components of the path need exist\n\
+ -L, --logical resolve `..' components before symlinks\n\
+ -P, --physical resolve symlinks as encountered (default)\n\
+ -q, --quiet suppress most error messages\n\
+ --relative-to=FILE print the resolved path relative to FILE\n\
+ --relative-base=FILE print absolute paths unless paths below FILE\n\
+ -s, --strip, --no-symlinks don't expand symlinks\n\
+ -z, --zero separate output with NUL rather than newline\n\
+\n\
+"), stdout);
+ fputs (HELP_OPTION_DESCRIPTION, stdout);
+ fputs (VERSION_OPTION_DESCRIPTION, stdout);
+ emit_ancillary_info ();
+ }
+ exit (status);
+}
+
+/* A wrapper around canonicalize_filename_mode(),
+ to call it twice when in LOGICAL mode. */
+static char *
+realpath_canon (const char *fname, int can_mode)
+{
+ char *can_fname = canonicalize_filename_mode (fname, can_mode);
+ if (logical && can_fname) /* canonicalize again to resolve symlinks. */
+ {
+ can_mode &= ~CAN_NOLINKS;
+ char *can_fname2 = canonicalize_filename_mode (can_fname, can_mode);
+ free (can_fname);
+ return can_fname2;
+ }
+ return can_fname;
+}
+
+/* Test whether prefix is parent or match of path. */
+static bool _GL_ATTRIBUTE_PURE
+path_prefix (const char *prefix, const char *path)
+{
+ while (*prefix && *path)
+ {
+ if (*prefix != *path)
+ break;
+ prefix++;
+ path++;
+ }
+ return (!*prefix && (*path == '/' || !*path));
+}
+
+/* Return the length of the longest common prefix
+ of PATH1 and PATH2, ensuring only full path components
+ are matched. Return 0 on no match. */
+static int _GL_ATTRIBUTE_PURE
+path_common_prefix (const char *path1, const char *path2)
+{
+ int i = 0;
+ int ret = 0;
+
+ while (*path1 && *path2)
+ {
+ if (*path1 != *path2)
+ break;
+ if (*path1 == '/')
+ ret = i;
+ path1++;
+ path2++;
+ i++;
+ }
+
+ if (!*path1 && !*path2)
+ ret = i;
+ if (!*path1 && *path2 == '/')
+ ret = i;
+ if (!*path2 && *path1 == '/')
+ ret = i;
+
+ return ret;
+}
+
+/* Output the relative representation if requested. */
+static bool
+relpath (const char *can_fname)
+{
+ if (can_relative_to)
+ {
+ /* Enforce --relative-base. */
+ if (can_relative_base)
+ {
+ if (!path_prefix (can_relative_base, can_fname)
+ || !path_prefix (can_relative_base, can_relative_to))
+ return false;
+ }
+
+ /* Skip the prefix common to --relative-to and path. */
+ int common_index = path_common_prefix (can_relative_to, can_fname);
+ const char *relto_suffix = can_relative_to + common_index;
+ const char *fname_suffix = can_fname + common_index;
+
+ /* Replace remaining components of --relative-to with '..', to get
+ to a common directory. Then output the remainder of fname. */
+ if (*relto_suffix)
+ {
+ ++relto_suffix;
+ printf ("%s", "..");
+ for (; *relto_suffix; ++relto_suffix)
+ {
+ if (*relto_suffix == '/')
+ printf ("%s", "/..");
+ }
+
+ printf ("%s", fname_suffix);
+ }
+ else
+ {
+ if (*fname_suffix)
+ printf ("%s", ++fname_suffix);
+ else
+ printf ("%c", '.');
+ }
+
+ putchar (use_nuls ? '\0' : '\n');
+
+ return true;
+ }
+
+ return false;
+}
+
+static bool
+isdir (const char *path)
+{
+ struct stat sb;
+ if (stat (path, &sb) != 0)
+ error (EXIT_FAILURE, errno, _("cannot stat %s"), quote (path));
+ return S_ISDIR (sb.st_mode);
+}
+
+static bool
+process_path (const char *fname, int can_mode)
+{
+ char *can_fname = realpath_canon (fname, can_mode);
+ if (!can_fname)
+ {
+ if (verbose)
+ error (0, errno, "%s", quote (fname));
+ return false;
+ }
+
+ if (!relpath (can_fname))
+ printf ("%s%c", can_fname, (use_nuls ? '\0' : '\n'));
+
+ free (can_fname);
+
+ return true;
+}
+
+int
+main (int argc, char **argv)
+{
+ bool ok = true;
+ int can_mode = CAN_ALL_BUT_LAST;
+ const char *relative_to = NULL;
+ const char *relative_base = NULL;
+
+ initialize_main (&argc, &argv);
+ set_program_name (argv[0]);
+ setlocale (LC_ALL, "");
+ bindtextdomain (PACKAGE, LOCALEDIR);
+ textdomain (PACKAGE);
+
+ atexit (close_stdout);
+
+ while (1)
+ {
+ int c = getopt_long (argc, argv, "eLmPqsz", longopts, NULL);
+ if (c == -1)
+ break;
+ switch (c)
+ {
+ case 'e':
+ can_mode &= ~CAN_MODE_MASK;
+ can_mode |= CAN_EXISTING;
+ break;
+ case 'm':
+ can_mode &= ~CAN_MODE_MASK;
+ can_mode |= CAN_MISSING;
+ break;
+ case 'L':
+ can_mode |= CAN_NOLINKS;
+ logical = true;
+ break;
+ case 's':
+ can_mode |= CAN_NOLINKS;
+ logical = false;
+ break;
+ case 'P':
+ can_mode &= ~CAN_NOLINKS;
+ logical = false;
+ break;
+ case 'q':
+ verbose = false;
+ break;
+ case 'z':
+ use_nuls = true;
+ break;
+ case RELATIVE_TO_OPTION:
+ relative_to = optarg;
+ break;
+ case RELATIVE_BASE_OPTION:
+ relative_base = optarg;
+ break;
+ case_GETOPT_HELP_CHAR;
+ case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
+ default:
+ usage (EXIT_FAILURE);
+ }
+ }
+
+ if (optind >= argc)
+ {
+ error (0, 0, _("missing operand"));
+ usage (EXIT_FAILURE);
+ }
+
+ if (relative_base && !relative_to)
+ {
+ error (0, 0, _("--relative-base requires --relative-to"));
+ usage (EXIT_FAILURE);
+ }
+
+ bool need_dir = (can_mode & CAN_MODE_MASK) == CAN_EXISTING;
+ if (relative_to)
+ {
+ can_relative_to = realpath_canon (relative_to, can_mode);
+ if (!can_relative_to)
+ error (EXIT_FAILURE, errno, "%s", quote (relative_to));
+ if (need_dir && !isdir (can_relative_to))
+ error (EXIT_FAILURE, ENOTDIR, "%s", quote (relative_to));
+ }
+ if (relative_base)
+ {
+ can_relative_base = realpath_canon (relative_base, can_mode);
+ if (!can_relative_base)
+ error (EXIT_FAILURE, errno, "%s", quote (relative_base));
+ if (need_dir && !isdir (can_relative_base))
+ error (EXIT_FAILURE, ENOTDIR, "%s", quote (relative_base));
+ }
+
+ for (; optind < argc; ++optind)
+ ok &= process_path (argv[optind], can_mode);
+
+ exit (ok ? EXIT_SUCCESS : EXIT_FAILURE);
+}
--- /dev/null
+#!/bin/sh
+# Validate realpath operation
+
+# Copyright (C) 2011-2012 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+. "${srcdir=.}/init.sh"; path_prepend_ ../src
+print_ver_ realpath
+
+# Setup dir, file, symlink structure
+
+mkdir -p dir1/dir2
+ln -s dir1/dir2 ldir2
+touch dir1/f dir1/dir2/f
+
+# Basic operaion
+realpath -Pqz . >/dev/null || fail=1
+# --relative-base and --relative-to require params
+realpath --relative-base --relative-to . && fail=1
+# --relative-base requires --relative-to
+realpath --relative-base=dir1 . && fail=1
+
+# -e --relative-* require directories
+realpath -e --relative-to=dir1/f --relative-base=. . && fail=1
+realpath -e --relative-to=dir1/ --relative-base=. . || fail=1
+
+# Note NUL params are unconditionally rejected by canonicalize_filename_mode
+realpath -m '' && fail=1
+
+# symlink resolution
+this=$(realpath .)
+test $(realpath $relative ldir2/..) = "$this/dir1" || fail=1
+test $(realpath -L $relative ldir2/..) = "$this" || fail=1
+test $(realpath -s $relative ldir2) = "$this/ldir2" || fail=1
+
+# relative string handling
+test $(realpath -m --relative-to=prefix prefixed/1) = '../prefixed/1' || fail=1
+test $(realpath -m --relative-to=prefixed prefix/1) = '../prefix/1' || fail=1
+test $(realpath -m --relative-to=prefixed prefixed/1) = '1' || fail=1
+
+Exit $fail