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32.2 Filesystem Utilities

Octave includes the following functions for renaming and deleting files, creating, deleting, and reading directories, and for getting information about the status of files.

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

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: [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: [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 dir, glob

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

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

Create a 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.

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)

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

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] = lstat (file)

Return a structure s containing the following information about file.

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 section 32.1 Timing Utilities.

mtime

Time of last modification in the same form as time values returned from time. See section 32.1 Timing Utilities.

ctime

Time of last file status change in the same form as time values returned from time. See section 32.1 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: [info, err, msg] = lstat (file)

See stat.

Function File: [status, msg, 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.

Built-in Function: glob (pattern)

Given an array of 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. Tilde expansion is performed on each of the patterns before looking for matching file names. For example,

glob ("/vm*")
     => "/vmlinuz"

See also dir, ls, stat, 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 matrix. 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: tilde_expand (string)

Performs 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.

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

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

See also glob

Function File: [status, msg, msgid] = copyfile (f1, f2, force)

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 force is given and equals the string "f" the copy operation will be forced.

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

See also glob, movefile

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

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

See also fullfile

Built-in Function: filesep ()

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

See also pathsep, dir, ls

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

Return a complete filename constructed from the given components.

See also fileparts

Function File: dir = tempdir ()

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

Function File: filename = tempname ()

This function is an alias for tmpnam.

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.

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