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36.2 Filesystem Utilities

Octave includes many utility functions for copying, moving, renaming, and deleting files; for creating, reading, and deleting directories; for retrieving status information on files; and for manipulating file and path names.

— Function File: [status, msg, msgid] = movefile (f1, f2)
— Function File: [status, msg, msgid] = movefile (f1, f2, 'f')

Move the file f1 to the new name f2. The name f1 may contain globbing patterns. If f1 expands to multiple file names, f2 must be a directory. If the force flag 'f' is given then any existing files will be overwritten without prompting.

If successful, status is 1, with msg and msgid empty character strings. Otherwise, status is 0, msg contains a system-dependent error message, and msgid contains a unique message identifier.

See also: rename, copyfile.

— Built-in Function: [err, msg] = rename (old, new)

Change the name of file old to new.

If successful, err is 0 and msg is an empty string. Otherwise, err is nonzero and msg contains a system-dependent error message.

See also: ls, dir.

— Function File: [status, msg, msgid] = copyfile (f1, f2)
— Function File: [status, msg, msgid] = copyfile (f1, f2, 'f')

Copy the file f1 to the new name f2. The name f1 may contain globbing patterns. If f1 expands to multiple file names, f2 must be a directory. If the force flag 'f' is given then existing destination files will be overwritten without prompting.

If successful, status is 1, with msg and msgid empty character strings. Otherwise, status is 0, msg contains a system-dependent error message, and msgid contains a unique message identifier.

See also: movefile.

— Built-in Function: [err, msg] = unlink (file)

Delete the file named file.

If successful, err is 0 and msg is an empty string. Otherwise, err is nonzero and msg contains a system-dependent error message.

— Built-in Function: [err, msg] = link (old, new)

Create a new link (also known as a hard link) to an existing file.

If successful, err is 0 and msg is an empty string. Otherwise, err is nonzero and msg contains a system-dependent error message.

See also: symlink.

— Built-in Function: [err, msg] = symlink (old, new)

Create a symbolic link new which contains the string old.

If successful, err is 0 and msg is an empty string. Otherwise, err is nonzero and msg contains a system-dependent error message.

See also: link, readlink.

— Built-in Function: [result, err, msg] = readlink (symlink)

Read the value of the symbolic link symlink.

If successful, result contains the contents of the symbolic link symlink, err is 0 and msg is an empty string. Otherwise, err is nonzero and msg contains a system-dependent error message.

See also: link, symlink.

— Built-in Function: [status, msg, msgid] = mkdir (dir)
— Built-in Function: [status, msg, msgid] = mkdir (parent, dir)

Create a directory named dir in the directory parent.

If successful, status is 1, with msg and msgid empty character strings. Otherwise, status is 0, msg contains a system-dependent error message, and msgid contains a unique message identifier.

See also: rmdir.

— Built-in Function: [status, msg, msgid] = rmdir (dir)
— Built-in Function: [status, msg, msgid] = rmdir (dir, "s")

Remove the directory named dir.

If successful, status is 1, with msg and msgid empty character strings. Otherwise, status is 0, msg contains a system-dependent error message, and msgid contains a unique message identifier.

If the optional second parameter is supplied with value "s", recursively remove all subdirectories as well.

See also: mkdir, confirm_recursive_rmdir.

— Built-in Function: val = confirm_recursive_rmdir ()
— Built-in Function: old_val = confirm_recursive_rmdir (new_val)
— Built-in Function: confirm_recursive_rmdir (new_val, "local")

Query or set the internal variable that controls whether Octave will ask for confirmation before recursively removing a directory tree.

When called from inside a function with the "local" option, the variable is changed locally for the function and any subroutines it calls. The original variable value is restored when exiting the function.

— Built-in Function: [err, msg] = mkfifo (name, mode)

Create a fifo special file named name with file mode mode

If successful, err is 0 and msg is an empty string. Otherwise, err is nonzero and msg contains a system-dependent error message.

— Built-in Function: umask (mask)

Set the permission mask for file creation. The parameter mask is an integer, interpreted as an octal number. If successful, returns the previous value of the mask (as an integer to be interpreted as an octal number); otherwise an error message is printed.

— Built-in Function: [info, err, msg] = stat (file)
— Built-in Function: [info, err, msg] = stat (fid)
— Built-in Function: [info, err, msg] = lstat (file)
— Built-in Function: [info, err, msg] = lstat (fid)

Return a structure info containing the following information about file or file identifier fid.

dev
ID of device containing a directory entry for this file.
ino
File number of the file.
mode
File mode, as an integer. Use the functions S_ISREG, S_ISDIR, S_ISCHR, S_ISBLK, S_ISFIFO, S_ISLNK, or S_ISSOCK to extract information from this value.
modestr
File mode, as a string of ten letters or dashes as would be returned by ls -l.
nlink
Number of links.
uid
User ID of file's owner.
gid
Group ID of file's group.
rdev
ID of device for block or character special files.
size
Size in bytes.
atime
Time of last access in the same form as time values returned from time. See Timing Utilities.
mtime
Time of last modification in the same form as time values returned from time. See Timing Utilities.
ctime
Time of last file status change in the same form as time values returned from time. See Timing Utilities.
blksize
Size of blocks in the file.
blocks
Number of blocks allocated for file.

If the call is successful err is 0 and msg is an empty string. If the file does not exist, or some other error occurs, s is an empty matrix, err is −1, and msg contains the corresponding system error message.

If file is a symbolic link, stat will return information about the actual file that is referenced by the link. Use lstat if you want information about the symbolic link itself.

For example:

          [s, err, msg] = stat ("/vmlinuz")
                ⇒ s =
                  {
                    atime = 855399756
                    rdev = 0
                    ctime = 847219094
                    uid = 0
                    size = 389218
                    blksize = 4096
                    mtime = 847219094
                    gid = 6
                    nlink = 1
                    blocks = 768
                    mode = -rw-r--r--
                    modestr = -rw-r--r--
                    ino = 9316
                    dev = 2049
                  }
               ⇒ err = 0
               ⇒ msg =

— Built-in Function: S_ISBLK (mode)

Return true if mode corresponds to a block device. The value of mode is assumed to be returned from a call to stat.

See also: stat, lstat.

— Built-in Function: S_ISCHR (mode)

Return true if mode corresponds to a character device. The value of mode is assumed to be returned from a call to stat.

See also: stat, lstat.

— Built-in Function: S_ISDIR (mode)

Return true if mode corresponds to a directory. The value of mode is assumed to be returned from a call to stat.

See also: stat, lstat.

— Built-in Function: S_ISFIFO (mode)

Return true if mode corresponds to a fifo. The value of mode is assumed to be returned from a call to stat.

See also: stat, lstat.

— Built-in Function: S_ISLNK (mode)

Return true if mode corresponds to a symbolic link. The value of mode is assumed to be returned from a call to stat.

See also: stat, lstat.

— Built-in Function: S_ISREG (mode)

Return true if mode corresponds to a regular file. The value of mode is assumed to be returned from a call to stat.

See also: stat, lstat.

— Built-in Function: S_ISSOCK (mode)

Return true if mode corresponds to a socket. The value of mode is assumed to be returned from a call to stat.

See also: stat, lstat.

— Function File: [status, result, msgid] = fileattrib (file)

Return information about file.

If successful, status is 1, with result containing a structure with the following fields:

Name
Full name of file.
archive
True if file is an archive (Windows).
system
True if file is a system file (Windows).
hidden
True if file is a hidden file (Windows).
directory
True if file is a directory.
UserRead
GroupRead
OtherRead
True if the user (group; other users) has read permission for file.
UserWrite
GroupWrite
OtherWrite
True if the user (group; other users) has write permission for file.
UserExecute
GroupExecute
OtherExecute
True if the user (group; other users) has execute permission for file.
If an attribute does not apply (i.e., archive on a Unix system) then the field is set to NaN.

With no input arguments, return information about the current directory.

If file contains globbing characters, return information about all the matching files.

See also: glob.

— Function File: isdir (f)

Return true if f is a directory.

See also: is_absolute_filename, is_rooted_relative_filename.

— Built-in Function: [files, err, msg] = readdir (dir)

Return names of the files in the directory dir as a cell array of strings. If an error occurs, return an empty cell array in files.

If successful, err is 0 and msg is an empty string. Otherwise, err is nonzero and msg contains a system-dependent error message.

See also: ls, dir, glob.

— Built-in Function: glob (pattern)

Given an array of pattern strings (as a char array or a cell array) in pattern, return a cell array of file names that match any of them, or an empty cell array if no patterns match. The pattern strings are interpreted as filename globbing patterns (as they are used by Unix shells). Within a pattern

*
matches any string, including the null string,
?
matches any single character, and
[...]
matches any of the enclosed characters.

Tilde expansion is performed on each of the patterns before looking for matching file names. For example:

          ls
               ⇒
                  file1  file2  file3  myfile1 myfile1b
          glob ("*file1")
               ⇒
                  {
                    [1,1] = file1
                    [2,1] = myfile1
                  }
          glob ("myfile?")
               ⇒
                  {
                    [1,1] = myfile1
                  }
          glob ("file[12]")
               ⇒
                  {
                    [1,1] = file1
                    [2,1] = file2
                  }

See also: ls, dir, readdir.

— Built-in Function: fnmatch (pattern, string)

Return 1 or zero for each element of string that matches any of the elements of the string array pattern, using the rules of filename pattern matching. For example:

          fnmatch ("a*b", {"ab"; "axyzb"; "xyzab"})
               ⇒ [ 1; 1; 0 ]

— Built-in Function: file_in_path (path, file)
— Built-in Function: file_in_path (path, file, "all")

Return the absolute name of file if it can be found in path. The value of path should be a colon-separated list of directories in the format described for path. If no file is found, return an empty character string. For example:

          file_in_path (EXEC_PATH, "sh")
               ⇒ "/bin/sh"

If the second argument is a cell array of strings, search each directory of the path for element of the cell array and return the first that matches.

If the third optional argument "all" is supplied, return a cell array containing the list of all files that have the same name in the path. If no files are found, return an empty cell array.

See also: file_in_loadpath.

— Built-in Function: filesep ()
— Built-in Function: filesep ('all')

Return the system-dependent character used to separate directory names.

If 'all' is given, the function returns all valid file separators in the form of a string. The list of file separators is system-dependent. It is ‘/’ (forward slash) under UNIX or Mac OS X, ‘/’ and ‘\’ (forward and backward slashes) under Windows.

See also: pathsep.

— Built-in Function: val = filemarker ()
— Built-in Function: filemarker (new_val)
— Built-in Function: filemarker (new_val, "local")

Query or set the character used to separate filename from the the subfunction names contained within the file. This can be used in a generic manner to interact with subfunctions. For example,

          help (["myfunc", filemarker, "mysubfunc"])

returns the help string associated with the sub-function mysubfunc of the function myfunc. Another use of filemarker is when debugging it allows easier placement of breakpoints within sub-functions. For example,

          dbstop (["myfunc", filemarker, "mysubfunc"])

will set a breakpoint at the first line of the subfunction mysubfunc.

When called from inside a function with the "local" option, the variable is changed locally for the function and any subroutines it calls. The original variable value is restored when exiting the function.

— Function File: [dir, name, ext, ver] = fileparts (filename)

Return the directory, name, extension, and version components of filename.

See also: fullfile.

— Function File: filename = fullfile (dir1, dir2, ..., file)

Return a complete filename constructed from the given components.

See also: fileparts.

— Built-in Function: tilde_expand (string)

Perform tilde expansion on string. If string begins with a tilde character, (‘~’), all of the characters preceding the first slash (or all characters, if there is no slash) are treated as a possible user name, and the tilde and the following characters up to the slash are replaced by the home directory of the named user. If the tilde is followed immediately by a slash, the tilde is replaced by the home directory of the user running Octave. For example:

          tilde_expand ("~joeuser/bin")
               ⇒ "/home/joeuser/bin"
          tilde_expand ("~/bin")
               ⇒ "/home/jwe/bin"

— Built-in Function: [cname, status, msg] canonicalize_file_name (name)

Return the canonical name of file name.

— Built-in Function: make_absolute_filename (file)

Return the full name of file, relative to the current directory.

See also: is_absolute_filename, is_rooted_relative_filename, isdir.

— Built-in Function: is_absolute_filename (file)

Return true if file is an absolute filename.

See also: is_rooted_relative_filename, make_absolute_filename, isdir.

— Built-in Function: is_rooted_relative_filename (file)

Return true if file is a rooted-relative filename.

See also: is_absolute_filename, make_absolute_filename, isdir.

— Built-in Function: P_tmpdir ()

Return the default name of the directory for temporary files on this system. The name of this directory is system dependent.

— Function File: dir = tempdir ()

Return the name of the system's directory for temporary files.

— Function File: tempname ()
— Function File: tempname (dir)
— Function File: tempname (dir, prefix)

This function is an alias for tmpnam.

See also: tmpnam.

— Function File: current_state recycle ()
— Function File: old_state recycle (new_state)

Query or set the preference for recycling deleted files.

Recycling files instead of permanently deleting them is currently not implemented in Octave. To help avoid accidental data loss it is an error to attempt enable file recycling.

See also: delete.