This section describes the functions for getting detailed information about a file, including the owner and group numbers, the number of names, the inode number, the size, and the times of access and modification.
This function returns t if the file filename1 is
newer than file filename2. If filename1 does not
exist, it returns
nil. If filename1 does exist, but
filename2 does not, it returns t.
In the following example, assume that the file aug-19 was written on the 19th, aug-20 was written on the 20th, and the file no-file doesn’t exist at all.
(file-newer-than-file-p "aug-19" "aug-20") ⇒ nil
(file-newer-than-file-p "aug-20" "aug-19") ⇒ t
(file-newer-than-file-p "aug-19" "no-file") ⇒ t
(file-newer-than-file-p "no-file" "aug-19") ⇒ nil
If the filename argument to the next two functions is a symbolic link, then these function do not replace it with its target. However, they both recursively follow symbolic links at all levels of parent directories.
file-attributesfilename &optional id-format
This function returns a list of attributes of file filename. If
the specified file cannot be opened, it returns
The optional parameter id-format specifies the preferred format
of attributes UID and GID (see below)—the
valid values are
'integer. The latter is
the default, but we plan to change that, so you should specify a
nil value for id-format if you use the returned
UID or GID.
The elements of the list, in order, are:
nilfor a text file.
add-name-to-filefunction (see Changing Files).
(sec-high sec-low microsec picosec). (This is similar to the value of
current-time; see Time of Day.) Note that on some FAT-based filesystems, only the date of last access is recorded, so this time will always hold the midnight of the day of last access.
(high . low), where low holds the low 16 bits. If the inode number is too wide for even that, the value is of the form
(high middle . low), where
highholds the high bits, middle the middle 24 bits, and low the low 16 bits.
For example, here are the file attributes for files.texi:
(file-attributes "files.texi" 'string) ⇒ (nil 1 "lh" "users" (20614 64019 50040 152000) (20000 23 0 0) (20614 64555 902289 872000) 122295 "-rw-rw-rw-" t (5888 2 . 43978) (15479 . 46724))
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 name ‘lh’.
is in the group with name ‘users’.
(20614 64019 50040 152000)
was last accessed on October 23, 2012, at 20:12:03.050040152 UTC.
(20000 23 0 0)
was last modified on July 15, 2001, at 08:53:43 UTC.
(20614 64555 902289 872000)
last had its status changed on October 23, 2012, at 20:20:59.902289872 UTC.
is 122295 bytes long. (It may not contain 122295 characters, though, if some of the bytes belong to multibyte sequences, and also if the end-of-line format is CR-LF.)
has a mode of read and write access for the owner, group, and world.
is merely a placeholder; it carries no information.
(5888 2 . 43978)
has an inode number of 6473924464520138.
(15479 . 46724)
is on the file-system device whose number is 1014478468.
This function returns the number of names (i.e., hard links) that
file filename has. If the file does not exist, 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 link to.
$ ls -l foo* -rw-rw-rw- 2 rms rms 4 Aug 19 01:27 foo -rw-rw-rw- 2 rms rms 4 Aug 19 01:27 foo1
(file-nlinks "foo") ⇒ 2
(file-nlinks "doesnt-exist") ⇒ nil