UTIMES(2) System Calls Manual UTIMES(2)

futimes, utimes — set file access and modification times

Standard C Library (libc, -lc)

#include <sys/time.h>

int
futimes(int fildes, const struct timeval times[2]);

int
utimes(const char *path, const struct timeval times[2]);

The access and modification times of the file named by path or referenced by fildes are changed as specified by the argument times.

If times is NULL, the access and modification times are set to the current time. The caller must be the owner of the file, have permission to write the file, or be the super-user.

If times is non-NULL, it is assumed to point to an array of two timeval structures. The access time is set to the value of the first element, and the modification time is set to the value of the second element. The caller must be the owner of the file or be the super-user.

In either case, the inode-change-time of the file is set to the current time.

In case of a symbolic link () function will set file access and modification times to the file the link references. The lutimes(3) function will set the access and modification times to the symbolic link file.

Upon successful completion, the value 0 is returned; otherwise the value -1 is returned and the global variable errno is set to indicate the error.

The utimes() system call will fail if:

[]
Search permission is denied for a component of the path prefix; or the times argument is NULL and the effective user ID of the process does not match the owner of the file, and is not the super-user, and write access is denied.
[]
path or times points outside the process's allocated address space.
[]
An I/O error occurs while reading or writing the affected inode.
[]
Too many symbolic links are encountered in translating the pathname. This is taken to be indicative of a looping symbolic link.
[]
A component of a pathname exceeds NAME_MAX characters, or an entire path name exceeded PATH_MAX characters.
[]
The named file does not exist.
[]
A component of the path prefix is not a directory.
[]
The times argument is not NULL and the calling process's effective user ID does not match the owner of the file and is not the super-user.
[]
The file system containing the file is mounted read-only.

The futimes() system call will fail if:

[]
fildes does not refer to a valid descriptor.

All of the functions will fail if:

[]
The times argument is NULL and the effective user ID of the process does not match the owner of the file, and is not the super-user, and write access is denied.
[]
times points outside the process's allocated address space.
[]
An I/O error occurred while reading or writing the affected inode.
[]
The times argument is not NULL and the calling process's effective user ID does not match the owner of the file and is not the super-user.
[]
The file system containing the file is mounted read-only.

stat(2), utime(3), lutimes(3)

The utimes() function call appeared in 4.2BSD. The futimes() function call first appeared in FreeBSD 3.0.

June 4, 1993 macOS 15.2