This section describes the functions for getting detailed information about a file, other than its contents. This information includes the mode bits that control access permission, the owner and group numbers, the number of names, the inode number, the size, and the times of access and modification.
This function returns the mode bits of filename, as an integer. The mode bits are also called the file permissions, and they specify access control in the usual Unix fashion. If the low-order bit is 1, then the file is executable by all users, if the second-lowest-order bit is 1, then the file is writable by all users, etc.
The highest value returnable is 4095 (7777 octal), meaning that everyone has read, write, and execute permission, that the SUID bit is set for both others and group, and that the sticky bit is set.
(file-modes "~/junk/diffs") ⇒ 492 ; Decimal integer.
(format "%o" 492) ⇒ "754" ; Convert to octal.
(set-file-modes "~/junk/diffs" 438) ⇒ nil
(format "%o" 438) ⇒ "666" ; Convert to octal.
% ls -l diffs -rw-rw-rw- 1 lewis 0 3063 Oct 30 16:00 diffs
This functions returns the number of names (i.e., hard links) that
file filename has. If the file does not exist, then this function
nil. Note that symbolic links have no effect on this
function, because they are not considered to be names of the files they
% ls -l foo* -rw-rw-rw- 2 rms 4 Aug 19 01:27 foo -rw-rw-rw- 2 rms 4 Aug 19 01:27 foo1
(file-nlinks "foo") ⇒ 2
(file-nlinks "doesnt-exist") ⇒ nil
This function returns a list of attributes of file filename. If
the specified file cannot be opened, it returns
The elements of the list, in order, are:
tfor a directory, a string for a symbolic link (the name linked to), or
nilfor a text file.
add-name-to-filefunction (see Changing File Attributes).
current-time; see Time of Day.)
tif the file’s GID would change if file were deleted and recreated;
For example, here are the file attributes for files.texi:
(file-attributes "files.texi") ⇒ (nil 1 2235 75 (8489 20284) (8489 20284) (8489 20285) 14906 "-rw-rw-rw-" nil 129500 -32252)
and here is how the result is interpreted:
is neither a directory nor a symbolic link.
has only one name (the name files.texi in the current default directory).
is owned by the user with UID 2235.
is in the group with GID 75.
was last accessed on Aug 19 00:09. Use
! convert this number into a time string. See Time Conversion.
was last modified on Aug 19 00:09.
last had its inode changed on Aug 19 00:09.
is 14906 characters long.
has a mode of read and write access for the owner, group, and world.
would retain the same GID if it were recreated.
has an inode number of 129500.
is on file system number -32252.